When do you use learn and when do you use teach?
This is a confusing piece of language usage and one that I often see and hear used incorrectly.
In English we have two separate words which distinguish whether we have gained or given the knowledge.
To talk about knowledge received or given in the past we use:
To learn - I learnt
To teach - I taught
"He learnt me something" isn't correct. Instead we should say:
"He taught me something"
He is doing the giving therefore we use "taught"
"I learnt him how to drive" is also not correct. Instead we should say:
"I taught him how to drive"
You are doing the giving therefore we use "taught"
"I learnt how to swim"
This is correct because you gained the knowledge to do something
Quick hint:
Next time you want to use learnt think about whether the person you are talking about gained or gave the knowledge.