---How much is the pair of shoes?----Thirty dollars ________ enough.A. is B. are C. be
—What’s this in English? —It’s __________ ruler.
—Thank you for your help. —_____________.
—Is this ______ pencil?—No, it’s not ______.
—.Where are the baseballs? —They are _______.
Mary’s room is big ______ tidy, ______ Bob’s room isn’t tidy.