The students couldn't help ______ when they heard the joke.
A. to laugh B. laugh C. laughing
Let’s put a square ________ sometimes.
A. on B. in C. for
-----_________did he come to Beijing.
-----Because he wanted to work here.
A. when B. What C. Why
_________ a cold, snowy day!
A. What B. What a C. How a
It’s cold this morning. Please __________ your winter jacket, Jenny and Li Ming.
A. put in B. put on C. put up
Look ! This is a square .
| A．正方形 | B．长方形 | C．圆 | D．三角形 |