. It’s no ____that you can’t find anybody here. They are all away at a meeting at the moment. 

China sent up two manned spaceships and they were also great scientific _______ in the world.

Gerneally speaking, it is difficult to breathe at a high       of Tibet (西藏).

 — Do you have any plans for this holiday?— To tell you the truth, I have nothing in        for holiday.

I can hardly say which dish is best –it’s simply a（n） _____ of personal taste．