(2014·石家庄高中复习教学质量检测)Seeing a large crowd at the street corner，I became aware of________unusual happening.

There isn’t ______ in the room.

All of the doctors have worked for a long time, but ________ of them stop to have a rest.

I visite Zhangjiajie during the summer vacation .It’s a pleasant trip, ____I’ll never forget. 

—Did you do __________ on vacation? ---Not really. I just stayed at home and helped mom.