四、根据图片及语境用情态动词may、might、should、must的适当形式填空
Dialogue 1
A: Look at that boy! Those books are falling. It

1. be difficult for him to hold them all.
B: Let's help him carry some.
Dialogue 2
A: That girl waiting at the bus stop looks anxious.

B: Yes, she 2. be in a hurry. She is always
looking at her watch.
Dialogue 3
A: Is that boy okay? He looks unwell.

B: He 3. have a stomachache. We
4. take him to the school doctor at
once.
Dialogue 4
A: That classmate seems stuck. He 5.

not know how to answer the questions.
B: But we 6. help him during the exam—
it's against the rules.

1. must 2. must 3. must
4. should 5. may/might 6. mustn't

【分析】
本题需结合每个对话的语境，判断说话者的语气（肯定推测、不确定推测、建议、禁止等），对应情态动词的用法来填空：1. 语境中男孩拿不住要掉的书，是肯定推测他难拿，用表肯定推测的must；2. 女孩焦虑且看表，肯定推测她赶时间，用must；3. 男孩不舒服，肯定推测他胃疼，用must；4. 建议立刻带他去校医，用表建议的should；5. 同学卡住，不确定推测他可能不会答题，用may/might；6. 考试帮人违反规则，表禁止，用mustn't。
【解析】
1. 句意：看那个男孩！那些书要掉了，他肯定很难拿住所有书。此处是对当前情况的肯定推测，用情态动词must。
2. 句意：是的，她肯定很匆忙。她总是看手表。结合语境，女孩焦虑且频繁看表，是肯定推测她赶时间，用must。
3. 句意：他肯定胃疼。结合上文“看起来不舒服”，是肯定推测身体状况，用must。
4. 句意：我们应该立刻带他去校医。此处是提出合理建议，用情态动词should。
5. 句意：他可能不知道怎么回答问题。结合上文“卡住”，是不确定的推测，用may或might均可。
6. 句意：但我们考试期间不能帮他——这违反规则。此处表禁止，用mustn't。
【答案】
1. must 2. must 3. must 4. should 5. may/might 6. mustn't
【知识点】
情态动词表推测、情态动词表建议、情态动词表禁止
【点评】
本题围绕日常对话场景考查情态动词的语境运用，需结合上下文逻辑判断推测的确定性、语气类型，属于基础题型，贴近实际应用。
【难度系数】
0.6