-Why are you so late getting home?
-Our teacher didn’t let us go____ we had finished our homework.
| A．because | B．when | C．if | D．until |
—Where is David?
—I think he________Australia．
| A．has gone to |
| B．has been |
| C．has gone |
| D．has been to |
—Have you packed the camera yet?
—Yes，of course．I________it last night．
| A．have packed |
| B．was packed |
| C．packed |
| D．had packed |
Homo erectus pekinensis(北京人)________in Zhoukoudian Village，on the Longgu Mountain，Fangshan District，Beijing．
| A．has discovered |
| B．was discovered |
| C．is discovered |
| D．will discover |
Grandma________us stories when we were very young．
| A．used to tell |
| B．was used to tell |
| C．is used to tell |
| D．was used to telling |
—________free education，the poor children in my hometown can go back to school．
—So can the children in my hometown．
| A．Thanks to |
| B．Instead of |
| C．As for |
| D．Towards |