助動詞問題（426〜450）

No.	問題	選択肢	答えと解説
426	She ___ have told me the truth earlier.	A. may B. might C. should D. must	解答と解説答え：C. should 忠告や非難を表す。
427	You ___ worry about the test. It's easy.	A. must B. shouldn't C. can't D. needn't	解答と解説答え：D. needn't 必要ないことを示す助動詞。
428	If you practice more, you ___ improve your score.	A. could B. can C. must D. shall	解答と解説答え：B. can 可能性・能力。
429	You ___ obey the rules at all times.	A. might B. must C. would D. may	解答と解説答え：B. must 義務・強制。
430	I ___ go now. It’s getting late.	A. must B. should C. could D. might	解答と解説答え：A. must 話し手の判断による必要性。
431	We ___ meet again someday.	A. should B. must C. may D. will	解答と解説答え：C. may 将来の可能性。
432	You ___ better not lie to her.	A. would B. had C. should D. must	解答と解説答え：B. had 「had better not」で「〜しない方がよい」
433	He ___ swim across the river when he was younger.	A. might B. could C. would D. must	解答と解説答え：B. could 過去の能力。
434	She ___ be upset if you don’t call her.	A. will B. must C. shall D. can	解答と解説答え：A. will 未来の確実な出来事。
435	You ___ have left your phone at home.	A. may B. can C. should D. will	解答と解説答え：A. may 推量・可能性。
436	I ___ go to the gym later today.	A. shall B. must C. might D. would	解答と解説答え：C. might 未確定な予定。
437	___ we take a break now?	A. Will B. May C. Shall D. Might	解答と解説答え：C. Shall 提案をする丁寧な表現。
438	You ___ be quiet during the test.	A. should B. might C. will D. could	解答と解説答え：A. should 義務に近い助言。
439	I ___ used to live in this neighborhood.	A. could B. might C. would D. must	解答と解説答え：C. would 過去の習慣。
440	She ___ be at home. The lights are off.	A. can’t B. must C. should D. will	解答と解説答え：A. can’t 推量の否定。
441	You ___ clean your room before guests arrive.	A. should B. shall C. might D. would	解答と解説答え：A. should 忠告や提案。
442	We ___ leave early to catch the train.	A. may B. should C. must D. will	解答と解説答え：C. must 必要性。
443	You ___ have misunderstood the question.	A. will B. should C. may D. must	解答と解説答え：C. may 推量。
444	I ___ go out if it doesn’t rain.	A. shall B. can C. would D. might	解答と解説答え：D. might 条件付きの未来の可能性。
445	They ___ prefer to stay at home tonight.	A. may B. must C. should D. shall	解答と解説答え：A. may 選択の可能性。
446	You ___ finish your homework before playing games.	A. must B. may C. will D. might	解答と解説答え：A. must 義務。
447	He ___ be sick. He looks pale.	A. shall B. must C. can D. might	解答と解説答え：B. must 推量の確信。
448	They ___ not agree with your idea.	A. can B. may C. would D. should	解答と解説答え：B. may 否定の可能性。
449	I ___ rather stay home than go out.	A. must B. would C. might D. shall	解答と解説答え：B. would 「would rather」で好みを表現。
450	You ___ have left the oven on!	A. must B. might C. could D. can	解答と解説答え：A. must 強い確信を示す。