Question

French is ......easy language ( use a determiner

Answer 1

an is the answer.........

Answer 2

Sugar costs thirty rupees a kilo is a correct verb. If something costs an amount of money that amount is needed in order to buy it, do it and pay it.

The amount of money is also required to buy something. If you use the verb is always depends on what is mean.

If the speaker means we must be careful how we spend our campaign money then costs is the right answer.