How long did it take you _____ the classroom yesterday.
Is that ____cat, Ross ? No, _____is white.
Our National Day falls ___ October 1 and thousands of cars pour into freeways ___ the early morning of the holiday.
—My sister is on holiday in Hainan. —I wonder ____.
Mr zhang speaks very loudly ___ all the people can hear him clearly.
—Have you done your homework?—No, I’ll finish it ___ ten minutes. A at B. in C. on D. after