His opinion is very important.

He is known as a person with learning.

This audio is very clear.

The sound was so quiet that I could hardly hear it.

He is an expert in comparative linguistics.

Computational linguistics is the study of analyzing human language with computers.

I am very interested in sociolinguistics.

He can speak many languages.

He received the letter challenging him to a duel and began preparing for the duel.

He is an expert in orthoepy, teaching pronunciation.