--- When did you buy this computer? It looks so new．
--- I it for only a couple of days．My sister bought it for me as a birthday present．
| A．bought | B．have bought |
| C．have had | D．had |
You should study harder______ it is too late to catch up.
| A．if | B．when | C．after | D．before |
Tell the boy the news. He is ______to understand it.
| A．enough old | B．enough young | C．old enough | D．young enough |
Class is over. Let’s stop______ a rest.
| A．having | B．to have | C．had | D．have |
--- _________ difference the day made! We were very happy.
| A．what | B．how | C．what a | D．how a |
--- I didn’t bring back anything from America.
--- _________ at all? Why not?
| A．Anything | B．Nothing | C．Something | D．Everything |