-- When do you need to pay the balance?
-- ______ December 31.
| A．In | B．By | C．During | D．Within |
—Why are you excited today?
—We have been told ______ a picnic this weekend.
| A．have | B．to have | C．having | D．had |
_______ great picture! Who painted it?
| A．How | B．What | C．How a | D．What a |
When you ______ at a restaurant, please order just enough food.
| A．eat | B．will eat | C．ate | D．have eaten |
Mr Lin, a famous writer, _______ our school last week.
| A．visits | B．will visit | C．is visiting | D．visited |
Smile to the world, ______ the world will smile back to you.
| A．nor | B．but | C．or | D．and |