The greetings used among friends or The greetings are used among friends?
I am confused with the below two sentences, which one is correct? or which one is more natural than the other?

1. The greetings used among friends.
2. the greetings are used among friends. [here is an ARE in the sentence.]

Question

The greetings used among friends or The greetings are used among  friends?
I am confused with the below two sentences, which one is correct? or which one is more natural than the other?

1. The greetings used among friends.
2. the greetings are used among friends. [here is an ARE in the sentence.]

Answer

one is a noun with a description, 1. means 朋友们一起使用的客套。 2. is a full sentence: 朋友们常常使用这种客套。