我们交个朋友吧。

You use this when you have just met someone. Maybe you had a great conversation at a cafe. Use it when you want to move from 'strangers' to 'acquaintances.' It is often followed by exchanging WeChat contact info. It is simple, direct, and very common in mainland China. Don't overthink the grammar; just say it with a smile. It is the ultimate social 'green light.'

Use it at networking events to sound approachable. It works great at parties when meeting friends of friends. If you are traveling and meet a helpful local, this is perfect. It is also common in online gaming or social media comments. Use it when the vibe is positive and you want to talk again. It is the standard 'first step' in Chinese social life.

Avoid using this in very high-stakes formal business meetings. It might sound a bit too casual for a CEO. Do not use it if the other person seems busy or annoyed. It can feel a bit 'salesy' if used by a shopkeeper. If you are on a romantic date, it might put you in the 'friend zone' too fast! Use it for platonic connections mostly.

In China, the concept of 关系 (guānxì) or 'connections' is huge. Making friends is the foundation of everything from business to daily life. Historically, 'making friends' was about building a support network. Today, it is the standard way to ask for someone's WeChat. It reflects a culture that values social harmony and expanding one's circle. It is a very 'proactive' social phrase.

You can say 我们可以交个朋友吗？ to be more polite. For a shorter version, try 交个朋友 in very casual settings. If you want to be humble, say 想跟你交个朋友 (I'd like to make friends with you). Some people use 加个微信吧 (Let's add WeChat) as a modern synonym. They both lead to the same result: a new contact in your phone!