There is an old joke about Chinese English learners:

A girl called Mary(definitly not her Chinese name) want to practise her oral English desperately when she had learnt some basic words and sentences.

One day,she happened to knock into a foreign tourist when walking in the Summer Palace absently.She apologized immadietely,"I'm sorry."

"I'm sorry ,too."said the foreigner.

She thought for a minute,and replied,"I'm sorry three."

The foreigner was confused,asked,"what are you sorry for?"

A smile appeared on Mary's face.

She said,"I'm sorry five."