There's always food in the freezer if need be.

如果需要，冰箱里总有食物。

They will act as my legal advisers if need be.

需要的话，他们会作我的法律顾问。

We'll bring him back to reason, by force if need be.

我们要使他恢复理智，必要时可用武力。

You can depend on him to rise to the occasion, if need be.

如果需要的话，你可依靠他来应付这个局面。

He faced the enemy valiantly, shuned no difficulties and dangers and would not hesitate to lay down his life if need be.

他英勇对敌，不避艰险，赴汤蹈火在所不计。