Where is my water bottle?

Today's rainfall was higher than average.

It's difficult to calculate the sum of this series.

He took a deep breath and inhaled the fresh air.

The dual number does not exist in English grammar.

The service life of this machine is 10 years.

I learned about Avogadro's number in chemistry class.

My hobby is playing wind instruments.

He is good at playing the trumpet.

The total number of this class is 30.