用英文回答a friend should be ？

A friend should be someone who can share your happiness and sorrow also can give your a hand in the first time when you in trobble.

A friend should be on your sincere.
一个朋友应该对你很诚恳。

A friend should be someone who would give you good advises all the time.

a friend should be support you forever

一个朋友应该

虚拟语气，表示...应该怎么做,职责义务

一个朋友应该