There are ______________ birds there in the sky.
| A．Million of | B．five millions of | C．millions of | D．five millions |
We'll never give up_______ on the project no matter how difficult it is.
| A．work | B．to work |
| C．working | D．worked |
You_______ buy a gift, but you can if you want to.
| A．must | B．mustn't |
| C．have to | D．don't have to |
Your house is always so tidy - how do you_______ it with three children?
| A．manage | B．produce |
| C．train | D．plan |
- Do you know Lucy well?
- Of course I do. We've been good friends_______ ten years ago.
| A．for | B．since |
| C．after | D．until |
You need two years of teaching_______ to get this job.
| A．information | B．experience |
| C．knowledge | D．condition |