A good book is a best friend who never turns his back upon us.
一本好书，莫逆之交。

A friend to all is a friend to none.
滥交者无友。

A friend is a second self.
朋友是另一个我。

A father is a treasure, a brother is a fort, but a friend is both.
父亲是财富，兄弟是安慰，朋友兼而有之。

A brother may not be a friend, but a friend will always be a brother.
兄弟不一定是朋友,而朋友总象兄弟一样

Your friend is the man who knows all about you and still likes you.
朋友是什么?就是知道你的一切而又喜欢上你的人

Without a friend the world is a wilderness.
没有朋友，世界就等於一片荒野。

There is no stronger bond of friendship than a mutual enemy.
具有共通敵人的友誼最牢固。

There are three kinds of friends: best friends, guest friends, and pest friends.
朋友有三种类:亲密无间的朋友,客人一样的朋友,难缠的朋友。

The friendship of a gentleman is insipid as water。
君子之交淡如水。

One friend in a lifetime is much; two are many; three are hardly possible
一生有一个朋友就够了,有两个则太多,三个则很难存在。

Keep the old, meet the new; one is gold, another is silver.
保有老朋友，认识新朋友；一个是黄金，一个是白银。

In time of prosperity, friends will be plenty; In time of adversity, not one amongst twenty.
富在深山有远亲，穷在闹市无人。

Good friends are like bras;snug,supportive and always close to the heart!
好友就像胸罩：温暖舒适，默默的支持着，而且永远贴近我们的心。

Friendship multiplies joys and divides griefs.
友谊可以增添欢乐，可以分担忧愁。

Friendship is love with understanding.
友谊是爱加上谅解
yikexun
Friendship cannot always stand on one side.
来而不往非礼也。