can 必要/意愿 She can really sing. (她真的会唱歌)
可能 That can indeed help. (这确实有帮助)
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could必要 He could swim when he was young. (他小时候会游泳)
可能 That could happen soon. (这很快就发生了)
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may 必要 May I stay? (我应该留下来吗?)
可能 That may be a problem. (这可能是个问题)
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might 可能 The weather might improve. (天气应该会变好)
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must 必要 Sam must go to school. (山姆必须要去学校了)
可能 It must be hot outside. (外面一定很热)
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shall 必要 You shall not pass. (你不可以过去)
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should 必要 You should stop that. (你应该停下)
可能 That should be surprising. (这应该是令人惊讶的)
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will 可能 She will try to lie. (她可能在撒谎)
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would 可能 Nothing would accomplish that. (什么都没有实现)
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Present Tense: Do / Does
I do my laundry on Saturdays. (我星期六洗衣服)
They do their chores when they arrive home. (他们回家后做家务)
He does nothing all day. (他整天什么都不做)
She does charity work when she has time. (她一有空就去做慈善工作)
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Past Tense: Did
I did my homework in record time. (我在创纪录的时间内完成了作业)
We did everything we could to help. (我们竭尽所能提供帮助)
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补充: 这些叫做modal verbs,你用这些modal verbs的后面的字要放原本字(没ing ,没ed),你有发现吗?你看到很多翻译都是一样华文意思的,别担心你看句子是怎么用就可以了理解。我给你这些例子要你慢慢理解了。