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

They______a certain amount of working experience through voluntary work. (烟台市)

It is 30 years since we last met. —— But I still remember the story, believe it or not, _________ we got lost on a rainy night.

__, he also had a son incollege who had taken a bank loan to pay for his studies.

What’s your favorite ________ —It’s science.