1. Explain it simply
A verb phrase can describe a noun when you place 的 between them.
The order is fixed: [verb phrase] + 的 + [noun].
The verb phrase comes first, then 的, then the noun it describes.
It means 'the noun that (does the verb)', like 'the book I bought' or 'the person who sings'.
2. Show examples
唱歌的人是我姐姐。
Chànggē de rén shì wǒ jiějie.
The person singing is my older sister.
verb phrase + 的 + noun
这是我买的书。
Zhè shì wǒ mǎi de shū.
This is the book I bought.
the book that I bought
妈妈做的饭很好吃。
Māma zuò de fàn hěn hǎochī.
The food mom made is delicious.
modifier + 的 + noun as subject
3. Share a tip
Keep the order fixed: the verb phrase comes before 的 and the noun comes after it. Never move the noun in front of the verb phrase, and never drop 的 - without it the phrase can't attach to the noun.