Many plants and animals ____________________ (危险的). We should take measures to save the endangered animals and plants. (danger)

____________________ (经理不在), we didn't know what to do. (with)

Take an umbrella with you ____________________ (以防下雨). (in case)

He hasn't been to Beijing. But he talked ____________________ (好像去过那里). (as if)

The machine is ____________________ (很难修). (repair)