The film brings the good cadre (干部) Jiao Yulu ______ on screen.
My parents told me _____ at the old people, it’s impolite.
You’d better_____ like that, or the teacher will be angry .
He looked ___________,but could see ____________.
I was doing my homework ________ my mother was cooking in the kitchen.
We should help our parents do some housework.The main structure of the sentence is _______.