He is an expert in theoretical physics.

He is good at explaining that theory.

He is known as a person with learning.

Since my new video game console has arrived, I'm going to invite my friends over for a party tonight.

My keys are inside the house.

He is quite a good cook.

I think his Japanese has improved quite a bit, hasn't it?

I am busy with work during the daytime.

He spends his time playing games every day.

We played tic-tac-toe in the park.