—Scissors can be dangerous, so you ____________ play with them.
— OK, I won’t.
| A．should | B．had better |
| C．shouldn’t | D．had not better |
My mother was waiting for me patiently _______ I was having my breakfast,.
| A．As | B．When | C．While | D．Since |
If there _____no buying and selling of a nimals, there___ no killing in nature.
| A．is ; is | B．will be ; will be |
| C．is ; will be | D．will be ; is |
--I don’t know if his uncle ________.
--- I think he ________ if it doesn’t rain .
| A．will come, comes | B．will come, will come |
| C．comes, comes | D．comes, will come |
It was not very warm ______ the sun came out.
| A．although | B．because |
| C．so | D．but |
The students hurried to the classroom ________ the bell rang.
| A．until | B．as soon as |
| C．if | D．so that |