tell off
Separable
Speak angrily to someone about bad behaviour
The teacher told him off for being late.
Usage
British English. American speakers say 'scold' or 'chew out'.
Separable
The object can go between the verb and the particle: turn the light off, or turn off the light. When the object is a pronoun it must go in the middle: turn it off, never turn off it.
Practise it
Add it to your daily practice or see every verb with up.
Further reading: tell off on Wiktionary (CC BY-SA).