【问】 我常弄混militate与mitigate这两个词。

【答】 militate作“发生作用或影响”(have an effect)解，通常用于指“不利的作用或影响”(与against连用)，但有时也用于指“有利的作用或影响”(与for或in favour of连用)：

1. His poor eyesight militated against his chances of becoming a pilot. (Crews)

他视力不好使他失去了当飞行员的机会。

2. Every fact militated against his argument.

每个事实都对他的论点不利。

3. The weather militated in favor of the crops.

这天气对庄稼的生长产生了良好的影响。

mitigate作“使减轻，使缓和”(reduce an unpleasant effect)解：

The doctor's cheerful manner mitigated the bad news. (Crews)

医生高兴的态度缓和了这个坏消息。