He is a true gentleman.

There are 20 students in our class.

That person is my friend.

I will turn twenty years old next year.

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

I have been studying Japanese for six months.

He picked up a six-chambered revolver.

It's difficult to calculate the area of this hexagon.

We have a responsibility to protect this world.

I wake up at six o'clock every day.