The twins don’t see their friends often. The reason is that they are very busy. (IF) → .............................

If the twins were not so busy, they would see their friends more often./If the twins were not so busy, they could see their friends more often./The twins would see their friends more often If they were not so busy./The twins could see their friends more often If they were not so busy./If the twins were not busy, they would see their friends more often./If the twins were not busy, they could see their friends more often./The twins would see their friends more often If they were not busy./The twins could see their friends more often If they were not busy.