根据句意,用所给动词的适当形式填空。
(1) You should ________ (be) careful.
(2) They ________ (fly) to Shanghai yesterday.
(3) It’s time for us ________ (have) a rest.
(4) —________ paper________ (make) from wood?
—Yes.
(5) The girl ________ (ride) the bike is in Class One. We ________ (call) her Mary.