My credit card uses a revolving payment system, so I pay a fixed amount every month.

I pay the rent every month.

The budget for this project is set and will not change.

This project meets a certain standard.

How much is the amount of money for this product?

I forgot my credit card.

We have to come up with a new method to solve this problem.

I go to the library every month.

I go to the library every month.

He attends a class to learn dialects every month.