when necessary

He seems to be making all the arrangements necessary so that he can continue trafficking in drugs when he turns himself in.

他似乎正在做好各种必要安排，以便他自首后还能继续贩毒。

Only use your car when absolutely necessary.

非用不可的时候再用你的汽车。

The government, when necessary, has recourse to the armed forces.

政府在必要时可以动用军队。

Praise them when necessary, but don't lay it on too thick.

必要时要表扬他们，但不能言过其实。

When necessary, instinct is the most reliable resource you can fall back on.

必要时，最保险的办法就是凭直觉判断。

The army needs men who are willing to fight, when necessary

军队需要在必要时愿意投入战斗的军人。

They are not afraid to tackle the issues or let the sparks fly when necessary.

他们不怕应对这些问题，也不怕必要时来一番激烈的争论。