你好。I have a very simple question to ask, but I couldn’t find a clear answer anywhere.
I have seen both 我朋友 and 我的朋友 used. Is there any rule on when you should use 的 for possessive and when it’s not necessary? Is it always interchangeable? For example, is it ok to say 我哥哥， 我老师， 我中文不是很好 etc? Or do I need 的 here?
I am not a native speaker and may well be corrected. Usually we say 我的朋友 or 我的哥哥， 我的老师 however it seems that for 我 especially, but also for other pronouns, it is sometimes quite OK to drop the 的 when speaking.
我哥哥，我朋友，我老婆，我中文不是很好 sounds quite colloquial.
e.g. 她是谁？她是我老婆！ 是谁把花瓶打碎了？ 是我哥哥。
However, if it’s in writing or formal speech, you do need to use 的.
e.g. 我的父母都是老师。 他的技艺很高超。
Thank you Steve and Wolf!