Most of my friends, Sandy, Millie and Allen, are all very kind to me.

You look very cool.–_____.

—Has your son come back from abroad for the winter vocation?—Yes. But he stayed at home for only a week. Now he _____ back to college. [ ]

My son has changed so much that I could hardly __________ his voice on the phone.

The box is used to collect waste which can be ________，such as plastic bottles and paper.