I’m writing _____ my friend. [ ]

The boy said ________ couldn’t he work out the problem but his teacher didn’t know how to do it.

There is _______ “u” and _______ “s” in the word “use”.

Where ________ you last night? I called you, but got no answer.—Sorry. I ________ out with my brother.

______ is “CHINA NEWS” shown on CCTV-4? —Every day.