The tense system

The tense system
There are three classes of verbs in Englis: auxiliary, modal verbs and full verbs.
1. Auxiliary verbs
The auxiliary verbs are be, do and have,
Be
1. Be is used with verb+ -ing to make continuous verb forms.
You re lying. (present)
They were reading. (past)
I have been swimming. (present perfect)
W ll be having dinner at 8 o clock. (future)
You must be joking! (infinitive)
2. Be is used with the past participle to make passive.
These books are printed in Hong Kong. (present)
Where were you born?
The car s been servied. (present perfect)
This work should be done soon. (infinitive)
Do
1. Do/does/did are used in the present simple and the past simple.
Do you smoke? (question)
She doesn t understands. (negative)
When did they arrive? (question)
2. Do/does/did are used to express emphasis when there is no other auxiliary.
I m not understanded in sport, but I do like tennis.
If only she had a car! She does have a car!
Why didn t you tell me? I did tell you!
Have
1. Have is used with the past participle to make perfect verb form.
Have you ever tried sushi? ( present)
My car had broken down before? (past)
I ll have finished soon. (future)
I d like to have met Napoleon. (infinitive)
Having had lunch, we tidied up. (participle)
Have and have got
Do you have any brothers and sisters?
Have you got any brothers and sisters?
Yes, I do. I have two brothers.
Yes, I have. I ve got two brothers.
2. Have to can be replaced with have got to for present obligation.
Do you have to go now?
Have you got to go now?
Yes, I do. I have to catch the bus.
Yes ,I have. I ve got to catch the bus.
3. OnIy forms of have (not have got) are used in all other tenses.
I had my first car when I was nineteen.
I ve had this car for two years.
I ll have a strawberry ice-cream, please.
I d had three cars by the time I was twenty.
I d like to have a dog.
He loves having a sports car.
4.Have ( not have got) is used in many expressions.
Have breakfast have a bath
have a party have a good time
have fun have a word with someone
5. Have got is generally more informal. It is use more in spoken English. than in written English. However, they are often interchangeable.