My parents told me _____ at the old people, it’s impolite.
| A．to laugh | B．laughing |
| C．laugh | D．not to laugh |
You’d better_____ like that, or the teacher will be angry .
| A．do | B．doing | C．not do | D．not doing |
He looked ___________,but could see ____________.
| A．careful; nothing | B．carefully; nothing |
| C．careful; anything | D．carefully;anything |
I was doing my homework ________ my mother was cooking in the kitchen.
| A．when | B．while | C．if | D．until |
We should help our parents do some housework.The main structure of the sentence is _______.
| A．S+V | B．S+V+DO+OC | C．S+V+P | D．S+V+IO+DO |