He is good at mathematics.

He took a deep breath, breathed in the fresh air, and showed a relaxed expression.

He is bad at remembering numbers.

Where is my canteen?

The water level of the river has suddenly risen.

This data is showing a significant change over time.

He solved the problem using numerals.

He went to Tokyo a few days ago.

Ah! I left something behind!

I have visited the Crystal Palace.