28. The Chairman thought ______ necessary _____ Professor Smith to speak at the meeting.
We are confident that the step the Chinese government has taken to cope with the current crisis is ______ of great significance.
The police are trying to find out the ____ of the woman murdered in the bathroom.
Li Qun, who graduated fromuniversity in South China, is now studying for her degree in ____ European country,
___ it rain tomorrow, we would have to cancel the football match.
-Sunday is a public holiday, ___ children should get close to nature. -But most of them have several lessons to attend.