—Did you call on any of your old friends when you returned to your hometown?—_______ of them. They were all very busy.

______ may have a chance to be successful if he tries his best.

——　Have you ever seen a whale alive? ——　Yes, I’ve seen ＿＿＿. 

Have you ever been to Mount Huangshan, _____ is famous for its towering pine forests and "sea of clouds"? 

I hate _____ when people talk with their mouths full.