My mother _______________ my aunt called her.

Do you enjoy traveling by air?—No, it’s ________ expensive.

As the winter holidays come, I’d love to sleep all day at home _____ have sports outdoor(户外).[ ]

Mr. Greento the manager now. You’d better call him later.

The survey shows that 200 students do different things during their vacations. ______ of them take classes according to the survey.