Nouns
的 for possession and description
的 links a describer to a noun, like the English apostrophe s and more besides.
Whatever describes a noun comes before it, joined by 的, de: my book, the teacher's name, the red car. With close relationships and very common pairings the 的 is usually dropped, so my mum is 我妈妈, wǒ māma, and a Chinese person is 中国人.
Examples
我的书wǒ de shūmy book
老师的名字lǎoshī de míngzithe teacher's name
我妈妈wǒ māmamy mumclose family, so no 的
红色的车hóngsè de chēthe red car
Watch out
The mistake this causes
Putting the describer after the noun, as French and Spanish do. In Chinese it always comes first.