Having said goodbye to their friends, they _______ for home.
A. set about B. set up C set down D. set off
Some kinds of animals can change their color with _______.
A. conditions B environment C. surroundingsD. situation
The headmaster has a particular way of_____her students nervousness when they speak.
| A． breaking down | B．breaking off | C． breaking up | D．breakfing away |
Gathering clouds________the coming storm.
| A． declared | B． turned out | C． appeared | D． announced |
In ____Chinese culture, marriage decisions were often made by parents for their children.
| A． traditional | B． historie | C． modern | D． remote |
_______man must fear when travelling in space is radiation from the sun.
| A． Which | B． How | C． What | D． That |