— Look! The girl with long hair is drawing a picture. Is she Sandy?— It ______ be her. I’m not sure.
—Who read the new book?Please tell me something about it.
—Have they finished the work? —Not .
—What do you our new car? —I think it is beautiful.
—Have you ever written a letter to your friend? —Yes, I.
—Have you received the books which ______ online? —Not yet.