____ you sing the English song?— Yes, I can.
Why are you so happy?—That’s because an old friend of is coming.
What on earth are the police busy with?—They have been looking into how the plane crash _______.
Some students often drop litter carelessly in our school. What can we do?- We can _______ some signs to remind them not to do that again.
I enjoy singing and I want ________ a member of the Music Club.