Chinese grammar: close possession N1+N2

Today we will introduce Chinese grammar: N1+N2. Sometimes you don't need 的 (de) to indicate possession. Normally possession is expressed with the particle 的. However, in some cases you can omit 的.

Structure

Normally possession is expressed with the particle 的. However, in some cases you can omit 的. This happens when the possession is about:
1. A close personal relationship (family and close friends)
2. An institutional or organizational relationship
In these cases 的 should be omitted (that is, it doesn't sound as natural if you put it in).

Examples

我 妈妈= My mom

If 的 was used in the above examples, it would create a sense of distance between the two, and possibly even imply that the relationship is not particularly close.