Using the correct tense and verb form is important in English grammar. Here's a simple rule to help you choose which tense to use - which tense you use depends on how you see the event or action.
Routine or permanent situations
- use the simple form.
For example, "I live in London" tells you that "live" is true all the time - London is my home.
"I lived in the countryside when I was a child" - this was a long-term situation in the past.
Temporary or continuing situations
- use the continuous form.
For example, "I'm working as a secretary at the moment" - the job isn't permanent and maybe I'm doing it for a while until I get another job.
"House prices are rising" - they are continuing to rise and haven't stopped rising yet.
"She was wearing a black dress" - she put it on before I saw her and she still wore it after I saw her - wearing the dress continued over a period of time.
Connecting different times
- use the perfect form to show that one event was completed before another, or to show that one situation continues from one time to another.
For example, "I have lived here for two years" - I started to live here two years ago and I still live here.
"I will have finished the report before next week" - some time before next week, but I don't know exactly when.
"He had studied law before he met her" - he studied law before he met her, but we don't know when.
I OR ME...
Be careful to use the pronouns I and me, he and him, she and her, we and us, they and them in the right place.
Use I, we, etc. when you are talking about someone who has done something (i.e. who is the subject of the sentence),
and use me, us, etc. when you are talking about someone who has had something done to them (i.e. who is the object of the sentence).
>People most often make mistakes over this when they are talking about more than one person:
* 'Me and Annie had a dog once'; 'Adrian and me were going out'. In these sentences you should use I, not me, because the two people are the subject in both. 'Annie and I had a dog once'; 'Adrian and I were going out'.
* 'Watch Helen and I while we show you'. You need me here, as the object of watch.
* 'Everything depends on you and I'. Use me, us, etc. after prepositions.
A good guide in cases like these is to see whether the sentence sounds right with only the pronoun. If 'Me had a dog' is wrong, then so is 'Annie and me had a dog'; if you wouldn't say 'Watch I while I show you', you shouldn't say 'Watch Helen and I'.
It's right to say 'between you and me', and wrong to say 'between you and I'. This is because a preposition such as 'between' should be followed by an object pronoun such as 'me', 'him', 'her', and 'us' rather than a subject pronoun such as 'I', 'he', 'she', and 'we'.
Saying ?Yes, I do. / No, I don?t? in English is more polite than just saying ?Yes. / No.? that?s why short answers are very commonly used.
To form the short answer, you use the first word from the question. (This is either an auxiliary verb or a form of ?be?.)
Use the long form (he does) in affirmative answers (yes).
Use the short form (he doesn?t) in negative answers (no).
Mind: If ?you? is the subject of the question, ?you? must be replaced by ?I? or ?we?.
If the question starts with ?are you?, ?are? must sometimes be replaced by ?am?.
adapted from: NDEC FAMILY