In this experiment, we will use an indicator to observe the reaction between acids and bases.

My younger sister is twenty-two years old.

Let's go to see a movie together.

I will turn twenty years old next year.

Our project is scheduled to be completed on the twentieth day of the month.

There is a two-story house.

What art thou doing?

Everyone, please have a good new year.

Our project is scheduled to be completed on the twenty-second day of the month.

The moon on the sixteenth night is beautiful, isn't it?