I will call him later.

I will study in the library after class.

The exam in the latter period was difficult.

He subsequently became a famous writer.

He left the station, departing from behind me.

He solved a large number of problems.

Understanding numbers is important for solving math problems.

He was bedridden with illness for several days.

I can't solve this problem because there are too many numbers.

I use a heart rate monitor during my daily exercise.