Definition Of Tense:
Tenses is defined as a verb that shows the time of an action (or) event.

Types of tenses:

There are three types of tenses, they are the following:

1. The Present Tense
2. The Past Tense
3. The Future Tense

Definition Of Present Tense:

A verb that refers to present time is said to be in the present tense.

1. Simple present
2. Present continuous
3. Present perfect
4. Present perfect continuous

It  is used to express the following:-
1)To express habitual action
(eg): He drinks tea everyday
2)To express general truths
(eg): The sun rises in the east
3)In exclamatory sentences beginning with here and there
(eg): Here comes the bus!
4)In vivid narrative, as substitute for simple past
(eg): Immediately sultan hurries to his capital
5)To express a future event
(eg): The train leaves at 5.30

2. Present Continuous Tense:

1) For an action going on at the time of speaking
(eg): she is singing
2) For a temporary action which may not happen at the time of speaking
(eg): I am reading “David copperfield” everyday  
3) For an action that have been already arranged to take place in the future
(eg): my uncle is arriving  tomorrow

3.Present Perfect Tense:

1) To indicate completed activities in the immediate past.
(eg): He has just gone out
2) To express past actions whose time is not given and not definite.
(eg): Mr.Hari has been to japan
3) To describe past events when we think more of their effect in the present than of the action itself
(eg): I have finished my work
4) To denote an action beginning at sometime in the past and continuing up to the present
(eg): I have known him for a long time 

4.Present Perfect Continuous:

The present perfect continuous is used for an action which began at sometime and is still continuing
(eg): He has been sleeping for five hours

Definition Of Past Tense:

A verb that refers to past time is said to be in the past tense.

1. Simple past
2. Past continuous
3. Past perfect
4. Past perfect continuous

1.Simple Past:

Simple past is used to indicate an action completed in the past
(eg): i) She left the school last year
ii) The teacher asked me why I  
was late   

2.Past Continuous:

The past continuous is used to denote an action going on at sometime in the past.
(eg): i) when I saw him he was playing 
chess
ii) The light went out while I was
reading   

3.Past Perfect:

1) The   past perfect describes an action completed before a certain moment in the past
(eg): I met him in Newdelhi in 1996. I     had seen him last five years before.
2) If two actions happened in the past it may be necessary to show which action happened earlier than the other
(eg): I had written the letter before he arrived.

4.Past Perfect Continuous:

1.The past perfect continuous is used for an action   that began before a certain point in  the past and continued upto that time.
2.past perfect con = had+been+verb+ing
(eg): They had been hunting for   house whole of last october

Definition Of Future Tense:

A verb that refers to future time is said to be in the future tense.

1. Simple future
2. Future continuous
3. Future perfect
4. Future perfect continuous

1.Simple Future:

1)  It is used to talk about things which we cannot control. It expresses the  future.
(eg): we shall know our exam results in may.
2)  We use this tense to talk about what we think (or) believe  will happen in the future
(eg): I’m sure Helen will get a first class tickets

2.Future Continuous:

1) We use future continuous tense to talk about actions which will be in progress at a time in the future
(eg): i) I suppose it will be raining when start.

3.Future Perfect:

1) The future perfect tense is used to talk about actions that will be completed by a certain future time.
(eg):i) I  shall have written my exercise  by then
ii) I  would have enjoyed my holidays  by next week

4.Future Perfect Continuous:

1)It  is used for actions which will be in progress over a period  of time that will end in the future.
(eg): By next march  we shall have been living here for four years
2)Future per con=will+have+been+verb+ing
(or)
would+have+been+verb+ing

Thats all Folks.......It was a Hard job.....wish I've choices to draw tables

well I've some questions for you......

QUESTIONS:

1. They ____ (work) on it for a month.
2. It _____ (rain) since 6 a.m.
3. Here _____ (come) kishore.
4. The little girls____ (have) a toy each.
5. God ____ (love) everyone.
6. The parrot ____ (fly) away.
7. The thief ____ (catch).
8. Rahul ____ (learn) telgu from me.
9. The dog ____ (bit) by a snake.
10. Radha ____ (meet) me tomorrow.

Answer it and enjoy....

Thankyou,

Rajkumar...