He was a swordsman named Zan in the past.

She gave birth to a baby in the maternity hospital.

This silkworm produces beautiful silk.

This lemon is sour.

We cannot live without oxygen.

He calculated the area of the triangle.

He is good at solving trigonometry problems.

He is good at arithmetic.

A day without seeing her feels like an eternity of waiting impatiently.

I make a sandwich every morning.