Scientists are trying their best to_______ ways to treat the terrible disease caused by Ebola(埃博拉).
He____know the answer, but I’m not sure.
My sister____Beijing tomorrow. She works there.
-My mother is ill in hospital. ——_______.
We can use QQ to talk with each other online. --Good! Will you please show me ______it?
My mother often spends 2 hours ______ housework every day.