Answer:
This seems to be more of an opinionated question, but I'll help out.
Good advice is advice anybody can apply to their own issues in life. (you should insert your own example of good advice though, not sure about that one)
He is a teacherMr. Surendra is a math teacher
Explanation:
If you're in doubt, say it out loud. It could also be 'the'.
A. Learning
The sentence should be, "Learning a new language as an adult is more difficult than learning one as a child."
