One can get rather intense about tenses, especially when you branch out into the confusing aspects of simple, continuous, and perfect forms of each tense. But as Maria (Julie Andrews) says (or sings) in The Sound of Music, ‘Let’s start at the very beginning’.
The three tenses are, of course, Present, Past, and Future, and affect the form of the verb when talking about things that have happened in the past, are occurring now, or are yet to happen. The past and present forms of a verb differ, but the future form uses what is called a compound verb.
For example, let’s look at the verb ‘go’. The forms are I go (present), I went (past), and I will go (future). But what if this is in the process of occurring as I say it. I would then say I am going. This is what is called the Continuous form of the present tense. Thus, the Continuous suggests that the action is happening as one talks or writes about it, and this can apply to the past or future. I will then say I was going (past) and I will be going (future).
The last aspect of the tenses is called the Perfect, and indicates that the action has been completed, even if it has yet to be. Say I had an appointment at 2pm tomorrow and a friend wanted to see me at 2.15pm. I will say to my friend that I will have gone by then. If the friend comes at 2.15pm without telling me that he is coming, then someone may tell him that he has gone (present perfect), which means he only just missed me. If the friend doesn’t come but tells me the next day that he was thinking of visiting me at 2.15pm, I would say I had gone (past perfect) to my appointment by that time.
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