Friends agree best at distance
朋友之间也会保持距离。
Friends are thieves of time
朋友是时间的窃贼。
Friends must part
再好的朋友也有分手的时候。
He is a good friend that speaks well of us behind our backs
背后说好话，才是真朋友。
I cannot be your friend and your flatterer too
朋友不能阿谀奉承。
Old friends and old wines are best
陈酒味醇，老友情深。
A faithful friend is the medicine of life
真诚的朋友如一剂生活的良药。
What is a friend? A single soul dewlling in two bodies
朋友是什么?两幅躯壳拥有同一个灵魂。
A friend in need is a friend indeed, (需要帮助时伸出援手的朋友才是真正的朋友。)
患难见真情。
Lend your money and lose your friend.
不要把钱借给朋友，如果借了，要么你朋友会因为你催还钱而不高兴，要么你会因为你朋友不还钱而不高兴。
You should not lend money to your friends; if you do, either you will have to bother your friend to repay the loan, which will make your friend resent you, or your friend will not repay the loan, which will make you resent your friend。
(这个不太符合中国人的观点吧...不过也有它的道理的)