Lee isn't in class. He must be sick.

李今天没有上课，他一定是病了。

youdao

He must be sick today.

他今天一定是生病了。

youdao

He must be sick for he looks so pale.

他一定是病了，因为他看上去是那么苍白。

youdao

Apple pundits were quick to infer that Chief Executive Steve Jobs must be sick after the computer maker said Tuesday that he won't be speaking at Macworld in January and this will be the company's last appearance at the conference.

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