Mr. Kushi is my best friend.

He sent me a 'kushi' (slang for a short message or information).

He excels in the ability to command English.

He made excellent use of that opportunity to fully demonstrate his abilities.

My grandmother has weak sight, so it's difficult for her to read small letters.

It's difficult to decipher this chemical equation.

He made good use of his English to give a presentation at an international conference.

He made excellent use of his knowledge to solve the problem.

He cut the apple into thin longitudinal slices.

He obtained a Bachelor of Science degree.