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!

He absorbs new information like a sponge soaking up water.

I think it's important to get enough sleep.

Due to his somnambulism, he may walk around unconsciously in the middle of the night.

I go to swimming lessons every Friday.

I took a sleeping pill last night and went to bed early.