Since he is still a green hand, he may make many mistakes.

He is still an immature pianist.

He is a famous author and a person who is respected by many people.

He ended up committing a serious mistake.

He spends a lot of time studying.

He reads a lot of books.

My homework is not finished yet.

My homework is still unfinished.

He was helping the villagers as a wizard.

I haven't done my homework yet.