By law,when one makes a large purchase, he should have _____ opportunity to change his mind.

That is to say，missing the chance means________for another year

Every hour and every minute ______precious to usbecause only six months are left for us to prepare for the college entranceexaminations

Although he was really disappointed, he _______ a weak smile.— He is always caring about others` feelings.

In those days, the old woman ________ sit at the door for hours, waiting for her son to return from abroad. [ ]