Listen! Who ____ behind the tree?A singsB. is singingC. singing
---- ______ Jackcomputer games? ----No. He is doing the homework.
—— Why do you like monkeys ? —— Because they are very ________.
My brother Peter is good at model planes.
—Bob, can you play violin? —Yes, but I don’t have violin.
— How long does it take to get to the library? — _______.