What a pity! Considering his ability and experience, he ____ have done better.

--- Isn’t it Ann’s husband over there?---- No, it ______ be him---I’m sure he doesn’t wear glasses.

Which _________ you rather __________, tea or coffee?

It doesn’t often snow in my hometown in winter, but it ___be rather cold sometimes. 

—Guess what; Yang Yang failed in the maths test .—How         it be？She is second to none in maths.