患难之交的英文：
[Literal Meaning]
scourge/disaster/aux./friendship
friends who have gone through sufferings and difficulties together

[解释]
在一起经历过艰难困苦的朋友。

[Explanation]
a true friend in adversity

[例子]
我们是患难之交，所以有很深的友谊。

[Example]
We are friends in adversity and have a sound friendship.

A friend in need is a friend indeed.
患难之交才是真正的朋友。

Nothing is dearer to a man than a friend in need.
患难之交最可贵。

You were a brick, a real friend in need.
你很够朋友，是真正的患难之交。

Fang Hung-chien and Miss T'ang laughed intimately, having now become comrades in adversity.
方鸿渐和唐小姐亲密地笑着，两人已成了患难之交。