The letter was passed from one to        until everyone had read it

—Could I smoke here?—I’d prefer _______if you don’t smoke in front of the children.

They like ___ better than mine.

In his lecture, the professor referred to the belief, in contrast to all other countries, ______ the elderly are wise, ______ is particularly dominant （占优势的） in the Chinese culture．

．—Do you think_____     worthwhile to go all the way to Los Angles to buy that computer?—Well ,I’m going to visit some relatives, too.