Everyone knows that _____ sun is in the center of the solar system（太阳系）
| A．a | B．an | C．the | D．/ |
You________such clothes because you are still a student.
| A．aren’t allowed to wearing | B．aren’t allowed to wear |
| C．aren’t allowed wearing | D．don’t allow to wear |
Lots of trees ________in our city over the years. It is becoming greener and greener!
| A．are planting | B．have planted |
| C．will be planted | D．have been planted |
-Hey, Molly, You______ on the phone just now. But you weren’t here and the man left a phone number.
-Oh? I was in the library.
| A．wanted | B．are wanted |
| C．were wanted | D．have wanted |
The little boy was made _____ again after his mother told him some jokes.
| A．laughed | B．laugh |
| C．to laugh | D．laughing |
— Food problem is becoming a big one in China!
—I think the food ________ before going to shops or supermarkets.
| A．is checked | B．is checking |
| C．should be checked | D．should check |