Hyperbole is the use of exaggeration
1. A million thanks is never enough for one big sacrifice.
2. I died a thousand deaths when my crush refused to dance with me.
3. Oh never, if i live a million, shall i feel such grievous pain.
4. She cried a river of tears when her mother died.
(A million thanks, A thousand deaths, A million, and A river of tears are exaggerations)