助動詞のmust - 英文法を覚えよう

【助動詞のmustとは何か？】

「must」は、強い義務や必然性、推量を表す助動詞であり、肯定文では「〜しなければならない」「〜しなくてはいけない」という意味になります。また、否定文では「〜してはいけない」「〜してはだめ」という意味になり、疑問文では「〜しなければならないのか？」という意味合いになります。基本的には、「must」は強い義務を表す助動詞として使われますが、時には、推量の意味合いを持つこともあります。

【助動詞のmustの肯定文】

「must」の肯定文は、以下のように使われます。

例文：

You must study hard for your exams. (試験のために一生懸命勉強しなければなりません。)
I must finish this report by tomorrow. (私は明日までにこのレポートを終わらせなければなりません。)

「must」は、直接的な命令や義務を表すときに使われます。また、「have to」や「need to」という表現と同様に、やむを得ない状況や自分自身で決めたルールなど、外部からの強い義務ではない場合でも使われることがあります。

【助動詞のmustの否定文】

「must」の否定文は、以下のように使われます。

例文：

You must not be late for the meeting. (会議に遅れてはいけません。)
I must not forget to buy milk on my way home. (帰りに牛乳を買うことを忘れてはいけません。)

「must not」は、明確な禁止事項を表すときに使われます。また、「can't」や「shouldn't」と同様に、自己判断や社会的規範など、外部からの強い義務ではない場合でも使われることがあります。ただし、「must not」の使用には注意が必要です。特に日常会話やビジネスシーンでは、「must not」は少々厳しい表現とされ、より丁寧な表現を使うことが推奨されます。

【助動詞のmustの疑問文】

「must」の疑問文は、以下のように使われます。

例文：

Must I submit this report by today? (私は今日中にこのレポートを提出しなければならないのでしょうか？)
Must we turn off the lights before leaving the office? (私たちはオフィスを出る前に電気を消さなければなりませんか？)

「must」の疑問文は、相手に直接的な命令や義務を尋ねるときに使われます。また、「have to」や「need to」と同様に、やむを得ない状況や自分自身で決めたルールなど、外部からの強い義務ではない場合でも使われることがあります。疑問文において、肯定・否定を表すには、「must」に続いて「not」を付けます。

【have to】

「must」は、「have to」という表現に置き換えることができます。「have to」は、強い義務を表す表現であり、「must」に近い意味を持ちますが、使い方やニュアンスには違いがあります。

例文：

I must finish this report by tomorrow. (私は明日までにこのレポートを仕上げなければなりません。)
I have to finish this report by tomorrow. (私は明日までにこのレポートを仕上げなければなりません。)
例文のように、「must」を「have to」に置き換えても、意味はほぼ同じですが、「must」はより強い義務を表現することがあります。また、「must」は、やむを得ない状況や自分自身で決めたルールなど、外部からの強い義務ではない場合でも使われることがありますが、「have to」は、主に外部からの強い義務を表現する場合に使われます。さらに、「have to」は、否定形と疑問形が「do not have to」と「do you have to」「does he have to」「did you have to」のように形が変化する点も異なります。

中学1年生	中学2年生	中学3年生
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フォニックス
フォニックス発音練習【1】短母音（A、E、I、O、U）、子音（B,K,D,F,G,H,J,L,M,N,P,Qu,R,S,T,V,W,X,Y,Z,softC,hardC,softG,hardG）
フォニックス発音練習【2】母音ペア（AI、AY、EI、IE、EA、EE、OA、OW、UE,UI、OI、OY、OU、OO、AU、AW）、Rが付いた母音（AR、ER、IR、UR、OR、ORE、EAR、AIR、ARE）、子音ダイヤグラフ（CH、SH、TH、CK、WH、GH、PH）、サイレントE
フォニックス発音練習【3】子音ブレンド（BL,CL,FL,GL,PL,BR,CR,DR,FR,GR,PR,TR,SC,SK,SM,SN,SP,ST,SW,SQU,SCR,SPL,SPR,STR,THR）

中学英単語
人称代名詞【1】 I, my, me, mine, you, your, you, yours, he, his, him, his, she, her, her, hers, it, its, it, we, our, us, ours, they, their, them, theirs
代名詞【2】 this, these, that, those, myself, yourself, himself, herself, ourselves, everybody, somebody, nobody, everyone, someone, anyone, none, everything, something, anything, nothing, each, other, another, all, both
be動詞・助動詞・疑問詞【3】 be, am, are, is, was, were, do, dose, did, can, cannot, could, will, would, may, might, must, shall, should, have to, who, whose, whom, what, which, when, where, why, how, how many, how much, how old
冠詞・間投詞・接続詞・省略形【4】 be, am, are, is, was, were, do, dose, did, can, cannot, could, will, would, may, might, must, shall, should, have to, who, whose, whom, what, which, when, where, why, how, how many, how much, how old
前置詞【5】 about, above, across, after, against, along, around, as, at, before, behind, below, beside, between, among, by, down, during, except, for, from, in, to, into, of, on, onto, minus, near, outside, over, since, than, through, toward, under, until, up, upon, with, without
名詞（数）【6】 zero, one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen, twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety, hundred, thousand, million
名詞（曜日・月・Ac-Af）【7】 Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, January, February, March, April, May, June, July, August, September, October, November, December, accident, acid rain, action, active volcano, activity, actor, actress, address, adult, advantage, adventure, advice, affection, Africa, afternoon
名詞（Ag-Ba）【8】 age, air, air conditioner, air pollution, airport, album, ambulance, America, American, amusement park, ancestor, anchor, animal, animation, ant, apple, architect, area, arm, art, artist, arts and crafts, Asia, assistance, astronaut, athlete, atomic bomb, attack, attention, aunt, Australia, autumn, baby, back
名詞（Ba-Bo）【9】 backyard, badge, bag, ball, balloon, ballpark, bank, barrier, baseball, basketball, bath, bathroom, bazaar, beach, bear, beauty, bed, beginner, beginning, Beijing, belief, bicycle, bike, biotechnology, bird, birthday, blanket, blood, blossom, board, boat, body, bomb
名詞（Bo-Ca）【10】 book, border, bottle, bottom, box, boy, boycott, braille, branch, Brazil, bread, breakfast, breath, breeze, bridge, British, broadcasting, brother, brotherhood, buffet, building, burger, bus, business, button, cafeteria, cage, cake, calligraphy, camera, campaign, Canada, cancer
名詞（Ca-Ch）【11】 candy, cap, capital, captain, car, card, care, carpenter, carrot, carton, cartoon, case, cat, cattle, cause, cave, CD, ceiling, cell, cent, center, centimeter, century, cereal, chain, chair, championship, chance, character, charity, chart, chemical, cherry
名詞（Ch-Co）【12】 chicken, child, children, China, Chinese, chopsticks, chorus, Christmas, church, city, class, classmate, classroom, clerk, clock, cloth, clothes, cloud, club, coffee, collection, college, color, comic, communication, company, computer, concert, conclusion, condominium, conductor, conference, connection
名詞（Co-De）【13】 convenience, conversation, cook, cooperation, corner, costume, country, countryside, couple, courage, course, cousin, cow, crane, creativity, creature, crop, cuisine, culture, cup, curry, curtain, custom, cut, dance, dancer, danger, date, daughter, day, deadline, death, decision
名詞（De-Do）【14】 deer, degree, democracy, demonstration, dentist, desert, desk, despair, detective, developing country, diary, dictionary, difference, difficulty, dignity, dinner, dinosaur, director, disaster, discussion, disease, display, distance, diver, doctor, dog, doll, dollar, dolphin, dome, door, doorbell, dot
名詞（Dr-Ev）【15】 drama, dream, dress, driver, drum, e-mail, e-pal, ear, earth, earthquake, east, echo, egg, Egypt, electricity, elephant, emergency, end, endangered animals, energy, engine, engineer, England, entrance, envelope, environment, episode, equality, era, eraser, Europe, evacuation, evening
名詞（Ex-Fi）【16】 examination, example, exchange, exhibition, exit, experience, expression, eye, eyesight, face, facility, fact, factory, fall, family, farewell, farm, farmer, fate, father, fault, favor, feeling, feet, fellow, fence, festival, fever, fiction, field, fine arts, finger, fire, firework
名詞（Fi-Ge）【17】 fish, fitting room, flag, flame, flight, floor, flower, flute, folk, food, football, foreigner, forest, fossil fuel, fountain, fox, frame, France, French fries, fridge, friend, friendship, frog, front, fruit, fun, future, game, garbage, garden, gas, gate, gentleman
名詞（Ge-Ha）【18】 German, Germany, gesture, gift, girl, glass, global warming, goal, God, gold, goodness, goose, gorilla, government, grade, grandchild, grandfather, grandmother, grass, grassland, green, greenhouse gases, greeting, ground, group, guest, guide, guitar, gull, habit, habitat, hair, Halloween
名詞（Ha-Ho）【19】 hamburger, hand, handkerchief, handle, harm, harvest, hat, hay fever, head, headache, health, heart, heat, heritage, hero, highland, hill, hint, history, hobby, hole, holiday, home, home economics, homepage, homestay, homework, honey, honor, horizon, horse, hospital, host
名詞（Ho-Ju）【20】 hotel, hour, house, humor, hunger, husband, idea, impact, importance, impossible, impression, India, Indian, influence, information, ink, insect, inspiration, instrument, interest, internet, interview, island, jam, Japan, Japanese, jellyfish, job, journey, joy, juice, jungle, justice
名詞（Ke-Li）【21】 key, kilometer, kind, kindness, king, kingdom, kitchen, kite, knee, knife, knowledge, koala, Korea, lady, lake, land, landmine, language, lavatory, law, lawyer, leader, leaf, leaves, left, leg, lesson, letter, library, life, lives, light, line
名詞（Li-Me）【22】 lion, liquid, locker, London, loss, lot, lullaby, lunch, machine, magic, man, men, manner, mansion, map, market, mask, master, match, mathematics, math, matter, meal, meaning, measure, meat, medal, medicine, meeting, member, memorial, memory
名詞（Me-Mt）【23】 mess, message, meter, Mexico, midnight, mile, milk, minister, minute, mirror, Miss, mistake, model, mom, moment, money, monkey, monster, monument, moon, moral education, morning, mother, motto, mountain, mouse, mouth, movement, movie, Mr., Mrs., Ms., Mt.
名詞（Mu-Nu）【24】 museum, music, musical, musician, nail, name, nap, nation, nature, neck, needle, neighbor, neighborhood, nephew, nest, net, New York, New Zealand, news, newspaper, nickname, niece, night, Nobel Peace Prize, noise, noon, north, northeast, nose, notebook, notice, number, nun
名詞（Nu-Pa）【25】 nurse, obstacle, occupation, ocean, octopus, office, officer, oil, opera, operator, opinion, orange, orchestra, order, organ, outside, oxygen, ozone, page, pain, paint, painter, painting, pair, paper, pardon, parent, park, parking, part, partner, party, passport
名詞（Pe-Pl）【26】 PE, peace, peel, pen, pencil, people, period, permission, person, pet, pharmacist, phone, photo, photographer, phrase, piano, picnic, picture, piece, pig, pillar, pilot, pink, pity, place, plan, plane, planet, plant, plastic, plate, player, playground
名詞（Pl-Qu）【27】 pleasure, pocket, poem, poet, point, poison, police, pollution, pool, population, post, poster, pot, potato, power, present, presentation, pressure, price, priest, principal, priority, problem, program, project, promise, pumpkin, purple, purpose, pyramid, queen, question, quiz
名詞（Ra-Ri）【28】 rabbit, race, racket, radio, rain, rainbow, rainforest, ramp, rat, ray, reason, recess, recipe, rectangle, recycling, refugee, relationship, relay, report, reporter, reproach, research, resource, rest, restaurant, restroom, rhythm, rice, rice cake, rider, right, ring, risk
名詞（Ri-Sh）【29】 river, road, rock, rocket, roof, room, rose, rule, ruler, sadness, safety, sale, salesclerk, salmon, salt, sanctuary, sand, scene, school, science, scientist, scissors, sculpture, sea, season, seat, secondhand store, secret, section, seed, sentence, service, shade
名詞（Sh-So）【30】 shape, sheep, sheet, shelf, ship, shirt, shoes, shop, shopping, shot, shoulder, shrine, side, sightseeing, sign, silver, singer, sister, site, situation, size, skill, skin, sky, slave, slum, smoke, snow, soccer, socks, social studies, softball, soldier
名詞（So-St）【31】 solution, son, song, sound, soup, south, souvenir, space, spaceship, Spain, speaker, specialist, speech, spoon, sport, spring, square, stadium, stairs, stamp, stapler, star, starvation, station, statue, stay, step, stick, stomach, stomachache, stone, store, storm
名詞（St-Te）【32】 story, stranger, street, string, struggle, student, style, subject, suburb, subway, success, summer, sun, sunrise, sunset, surface, survey, sweater, sword, symbol, system, T-shirt, table, tag, tail, task, tea, teacher, teacup, team, tear, telephone, telescope
名詞（Te-To）【33】 television, temper, temperature, temple, tennis, test, textbook, Thanksgiving Day, theater, theme, thief, thing, thought, ticket, tiger, time, tissue, toast, today, toe, toilet, tomato, tomorrow, ton, tongue, tonight, tooth, teeth, toothache, top, tower, town, toy
名詞（Tr-Un）【34】 track, track and field, trade, tradition, traffic, tragedy, train, trap, trash, travel, tray, treasure, tree, triangle, trick, trip, trouble, truck, trust, truth, tube, turkey, turn, turtle, TV, U.K., umbrella, United Nations, uncle, unicycle, uniform, United States, unity
名詞（Un-We）【35】 universal design, university, use, vacation, value, variety, vegetable, vending machine, vet, victim, video, video game, view, village, violin, visit, visitor, voice, volcano, volleyball, volume, volunteer, vulture, waitress, wall, wallet, war, water, waterfall, way, weapon, weather, weather forecast
名詞（We-Zo）【36】 web, week, weekend, well, west, whale, wheel, wheelchair, wife, wind, windmill, window, wine, wing, winner, winter, wish, witch, wolf, woman, wood, word, work, worker, world, World Heritage Site, yacht, year, yellow, yen, yesterday, zebra, zoo
形容詞（順序を表す言葉）【37】 first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, sixteenth, seventeenth, eighteenth, nineteenth, twentieth, thirtieth, fortieth, fiftieth, sixtieth, seventieth, eightieth, ninetieth, hundredth, thousandth, millionth
形容詞（Ab-Ce）【38】 able, active, adult, afraid, all, American, ancient, angry, another, any, artificial, asleep, atomic, awesome, bad, ill, worse, worst, bare, basic, beautiful, big, black, blind, blue, bored, boring, born, both, breathtaking, bright, British, brown, busy, careful, centigrade, certain
形容詞（Ch-Dr）【39】 cheap, cheerful, chemical, Chinese, civil, clean, clever, close, cloudy, cold, colorful, comfortable, commercial, common, compulsory, conceited, confused, convenient, cool, correct, creative, crowded, cute, daily, dangerous, dark, dead, deaf, dear, deep, delicious, depressed, different, difficult, dirty, disabled, disappointed, dry
形容詞（Dy-Fr）【40】 dying, each, easy, economic, efficient, elderly, elegant, elementary, else, embarrassed, empty, equal, even, every, exact, excited, exciting, expensive, fair, faithful, famous, far, fast, favorite, few, fine, fit, fond, foolish, foreign, former, foster, free, fresh, friendly, frightened, frustrated
形容詞（Fu-La）【41】 full, funny, German, glad, global, good, well, better, best, great, greedy, half, happy, hard, healthy, heavy, high, honest, hot, huge, human, hungry, important, impossible, Indian, industrial, injured, integrated, intense, interested, interesting, international, itchy, Japanese, junior, kind, large
形容詞（La-No）【42】 last, late, light, little, less, least, living, long, loud, lucky, major, many, much, more, most, master, meaningful, medium, memorial, mighty, military, minor, miserable, modern, musical, narrow, national, natural, naughty, necessary, neither, nervous, new, next, nice, noble
形容詞（No-Re）【43】 noisy, northeast, northern, nuclear, official, old, only, open, opposite, optimistic, ordinary, original, other, outside, own, pale, paralyzed, particular, peaceful, perfect, plastic, pleasant, polite, political, poor, popular, positive, possible, present, pretty, proud, public, quiet, rainy, ready, real, red
形容詞（Re-St）【44】 regular, relaxed, responsible, rich, ridiculous, right, round, sacred, sad, safe, same, scary, selfish, senior, serious, several, short, shy, sick, silent, silly, similar, simple, sleepy, slow, small, smart, smooth, snowy, sociable, soft, some, sore, sorry, sour, special, stiff, straight
形容詞（St-Yo）【45】 strange, strong, stupid, such, sunny, sure, sweet, tall, terrible, thirsty, tired, tourist, traditional, true, unbelievable, unclean, underground, unequal, unhappy, useful, usual, vast, virtual, warm, weak, welcome, western, white, whole, wide, wild, willing, windy, wonderful, worth, wrong, young
動詞（Ac-Br）【46】 act, add, admire, advertise, agree, allow, amaze, answer, appear, arrest, arrive, ask, assist, attack, bark, bear, become, became, begin, began, begun, believe, belong, blame, blow, blew, boil, border, borrow, bother, break, broke, broken
動詞（Br-Co）【47】 bring, brought, broaden, brush, build, built, bump, burn, bury, buy, bought, call, campaign, care, carry, catch, caught, cause, celebrate, change, chew, choose, chose, clean, climb, close, collect, come, came, communicate, compare, complain, contact
動詞（Co-Ea）【48】 continue, control, cook, cost, cough, count, cover, create, cross, cry, decide, decorate, decrease, develop, die, disagree, disappear, discover, displace, display, do, does, did, done, draw, drew, dream, drink, drank, drunk, drive, drop, dump, earn
動詞（Ea-Fu）【49】 eat, ate, eaten, elect, enjoy, enter, excuse, expect, explain, explode, export, fail, fall, fell, fascinate, fasten, feel, felt, fight, fought, fill, find, found, finish, float, fly, flew, fold, follow, forget, forgot, forgive, fulfill
動詞（Ga-Hu）【50】 gather, get, got, give, gave, given, go, went, gone, graduate, grow, grew, guess, guide, handle, hang, happen, harm, hate, have, has, had, heal, hear, heard, help, hide, hit, hold, held, hope, hurry, hurt
動詞（Im-Le）【51】 imagine, increase, injure, inspire, insult, interest, introduce, invent, investigate, invite, join, judge, jump, keep, kill, knit, knock, know, knew, known, land, last, laugh, launch, lay, laid, lead, led, learn, leave, lend, lent
動詞（Li-Pa）【52】 lie, lay, lain, lied, lift, like, listen, live, locate, look, lose, make, made, marry, master, mean, meant, meet, met, mind, miss, move, need, nod, offer, open, order, overcome, paint, park, participate, pass, pay, peel
動詞（Pi-Re）【53】 pick, plan, plant, play, please, poison, pollute, post, practice, prefer, prepare, present, print, produce, protect, provide, publish, pull, punish, push, put, rain, raise, reach, react, read, realize, rebuild, receive, recognize, recycle, reduce, refresh
動詞（Re-So）【54】 reject, relay, release, remain, remember, remind, remove, report, represent, reproach, rescue, research, respect, respond, return, reuse, ride, rode, ridden, rise, run, ran, run, save, say, said, scare, scold, search, see, saw, seen, seem, sell, sold
動詞（Se-St）【55】 send, sent, separate, sew, shake, sheet, shine, shoot, shop, shout, show, shut, sing, sang, sung, sit, sat, ski, sleep, smell, smile, smoke, snow, solve, sort, sound, speak, spoke, spoken, spell, spend, stand, start, starve, stay
動詞（St-Tr）【56】 sting, stop, strive, struggle, study, succeed, suffer, support, suppose, surf, surprise, surround, survive, swallow, swim, swam, swum, take, took, taken, talk, teach, taught, tease, tell, told, thank, think, throw, threw, thrown, touch, travel, treat
動詞（Tr-Ya）【57】 trust, try, turn, uncover, understand, understood, use, visit, wait, wake, woke, woken, walk, want, wash, waste, watch, weaken, wear, weigh, whisper, whistle, win, won, wish, wonder, work, worry, wrap, wrestle, write, wrote, written, yacht
副詞（A.-Fi）【58】 a.m., about, abroad, again, ago, almost, alone, aloud, already, also, always, anytime, anywhere, away, back, best, better, carefully, certainly, cheerfully, clearly, closely, definitely, downstairs, early, easily, either, else, enough, especially, even, ever, everywhere, fast, finally
副詞（Fl-Ra）【59】 fluently, forever, forward, happily, here, incredibly, instead, just, later, long, maybe, more, most, never, no, northeast, not, now, o’clock, off, often, OK, once, out, outside, over, p.m., perhaps, please, precisely, quickly, quietly, quite, rather
副詞（Re-Ye）【60】 ready, really, right, round, sadly, sincerely, slowly, so, someday, somehow, sometimes, soon, still, straight, strongly, suddenly, sure, then, there, tightly, together, tomorrow, tonight, too, truly, unfairly, up, usually, very, well, worst, yes, yesterday, yet