Conditionals are used to express both real, likely and unreal situations. As a result, tenses used with them are not flat; they change. That is why the difference between ‘If I arrive’ and ‘If I had ...

To establish the difference between the use of ‘has/have’ and that of ‘had’, one needs to understand the essence of the past perfect tense. When two things occurred in the past, the past perfect tense ...