be separated

separate

separately

We must separate bad apples from good ones.

(5)A fence _______ the garden from the sidewalk.

A. divides B. separates C. breaks D. fixes

B。separate"分开"。

考点4. combine vt.& vi. (使)联合;(使)结合

Eco-travel is a form of travel that combines normal tourism with learning.

Patience combined with diligence is necessary to success.

耐心结合勤奋是成功所必需的。

combine vi.& vt. 联合

combine ... with 与......结合(化合)

combine ...and... 与......结合

(1)We can't always ____________(结合)work with pleasure.

(2)Bad planning, ___________(再加上)with bad luck, led to

the company's failure.

(3)我们应该使理论和实际相结合。

(写作小练笔：主谓宾+介词；theory, practice)

combine

combined

__________________________________________

(4)You are supposed to ________ hydrogen with oxygen to finish

the test.

A. mix B. put C. compare D. combine

D。combine ... with 与......结合(化合)。

考点5. watch out注意；当心

Watch out for dangers, such as spiders, snakes or poisonous plants.

I said I should be sick, and that I must watch out for symptoms.

我说过我一定是有病了，我得留意一下症状。

watch out (for) 注意；当心

take care 注意；当心

be careful 注意；当心

keep a close watch on 密切注意

on the watch for 警戒；注意

look out 留神；注意

We should combine theory with practice.

(1)You should _______________(防备)thief.

(2)____________(小心)! There's a car coming.