A friend is easier lost than found
得朋友難，失朋友易。

A friend in need is a friend indeed.
患難見真情。

A friend is never known till a man has need.
需要之時方知友。

A friend without faults will never be found.
沒有十全十美的朋友。

Between friends all is common.
朋友之間不分彼此。

He is a good friend that speaks well of us behind our backs.
背后說好話，才是真朋友。

Life without a friend is death.
沒有朋友，雖生猶死。

Misfortune tests the sincerity of friends.
患難見真情。