①变化中的世界
②长假过后
③巨大的变化
④如此(那么)多的人
⑤提高我的英语水平
⑥我感觉不舒服
①越来越漂亮
②从…回来
③发生
④拍照
⑤顺便问一下
⑥很长时间
②We (clean) the classroom yesterday afternoon .
②He not ( post)the letter an hour ago .
B:Yes, he .
A:When he (arrive) ?
B:Three days ago .
—Oh,let's go to the classroom.
—They _____ England.
—I've no idea. I _____ there.
—Yes. I _____ him in the library five minutes ago.
B: No, never.
—B: Sorry , I don't .But I think he ___the library.