精讲课 笔记随视频锁定
情态动词表推测+非动词

右侧笔记支持独立滚动。边听名师连读拆解，边对照右侧的语法事实与统计数据笔记。

must be 表推测 表实义
She must be busy. 他现在肯定很忙。 他必须很忙。
He must be ill. 他肯定是生病了 他必须生病。
They must be here at seven o'clock. 他们肯定在7点到这里。（不能推测未来） 他们必须在7点到这里。
He must be German. 他一定是德国人。 他必须是德国人。
They must be in London next week. (下周是未来，不能表推测) 他们下周必须在伦敦。
She must be a teacher. 她一定是一位老师。 她必须是老师。
You must be at the office early tomorrow. (明天是未来) 你明天必须很早到办公室。

不同词性的推测

形容词
  • He can't be ill. ⇒ He must be tired.
  • He can't be the youngest. ⇒ He must be the oldest. 形容词最高级
  • He can't be reading. ⇒ He must be sleeping. 现在进行时 + 表推测
名词
  • It can't be my new hat. ⇒ It must be my old one.
  • She can't be Danish. ⇒ She must be Swedish.
  • He can't be a dentist. ⇒ He must be a doctor.
数词
  • She can't be forty. ⇒ She must be fifty.
  • It can't be the 20th. ⇒ It must be the 21st.

I think he is probably…改写以下句子

  • He must be home before six o'clock. ⇒ I think he is probably tired before six o'clock.
  • He has to be home before six o'clock. ⇒ I think he is probably home before six o'clock.
  • He must be busy. ⇒ I think he is probably busy.
  • He must / has to be here at six o'clock. ⇒ I think he is probably here at six o'clock.