singular or a plural verb after "и..., и ..."?

Question

Do I need to place a singular or a plural verb after "и..., и ..."?For example:> И Россия, и Франция вxод(**и/я**)т во Всемирную Торговую Организацию.

Answer 1

We need to use plural, because there are several countries(plural). For example: И Россия, и Франция, и Великобритания участвовали в войне против Германии.

Answer 2

Входят, because you agree the verb with plural ; и is only for intensification, i.e. Both Russia and France are...