虚拟语气条件状语从句中表将来用should的话 If we should go swim,we would very h

虚拟语气条件状语从句中表将来用should的话 If we should go swim,we would very happy.可以说go swim 还是 go swimming?这 这句是虚拟语气吗?
我自己写的这句话对吗？为什么是 would be very happy呢？