What happened to your brother?— He slipped on the icy road after a bus, and had his leg broken.[ ]

Could you tell me______–Maybe in a week. I’m not quite sure.

It is uncertain ________ side effect the medicine will bring about, although about two thousand patients have taken it.(2010·浙江)

Not only the students but also their teacher _______ about the four people.

Mr. Smith, _______ of the ______ speech, started to read a novel.