Definition Of Present Tenses:

The present tense may refer to an action or event that is ongoing or that takes place at the present moment. However, because the present tense in English can also be used to express a range of other meanings (including references to past and future events, depending on the context), it is sometimes described as being "unmarked for time."

Present Simple Tense

It is used to express an action in present time, habitual or usual actions or daily event or universal fact. It is used to express an action in present time which is usually done on a regular basis. For example a student says, “I go to school”. It is a daily activity of a student to go to school, so such actions are expressed by present simple tense. Another example is, “I work in a factory”. It tells about a usual action of a person that he works in a factory on regular basis.

Rules. 1st form of verb or base verb is used as main verb in sentence.

Structure of sentence – Rules

Positive Sentence

   • Subject + Main verb + Object
   • Subject + 1st form of verb (or base verb) + Object

Note: If the subject in a sentence is “he, she, it, singular or proper noun” then “s” or “es” is added to the first form of verb or base form in the sentence.

Examples.

I write a letter.

He gets up early in the morning.

Sun rises in east.

Negative Sentences
   • Subject + auxiliary verb +NOT + Main verb +object
   • Subject + Do not/Does not + 1st form of verb (or base form) + object

Examples.
         I do not write a letter.
         He does not get up early in the morning.
         Sun does not rise in east.

Note: In negative sentence auxiliary verb “do or does” along with “not” is used. If the subject in a sentence is “he, she, it, singular or proper noun”, then “Does not” is used after subject in sentence. If subject is “I, we, they, you or plural” then “Do not” is used after subject in sentence. “s” or “es” is not added to main verb in negative sentence

Interrogative Sentence
   • Auxiliary verb + Subject + Main verb + Object
   • Do/Does + Subject + 1st for of verb (or base verb) + Object

Examples.
         Do I write a letter?
         Does he get up early in the morning?
         Does sun rise in east?

Note: If the subject in a sentence is “he, she, it, singular or proper noun” the sentence is started with Auxiliary verb “Does”. If the subject in a sentence is “I, we, they, you or plural” the sentence is started with auxiliary verb “Do”. “s” or “es” is not added to main verb in Interrogative sentence

More Examples

Positive Sentences
          I sing a song.
          He drinks water
          They read lessons
          Birds chirp
          John reaches home in time.
          Water maintains its surface level.

Negative Sentences
          I do not sing a song
          He does not drink water
          They do not read lessons
          Birds do not chirp
          John does not reach home in time.
          Water does not maintain its surface level.

Interrogative Sentences
        Do I sing a song?
        Does he drink water?
        Do they read lessons?
        Do birds chirp?
        Does John reach home in time?
        Does water maintain its surface level?

Present Continuous Tense

It is used to express a continued or ongoing action at present time. It expresses an action which is in progress at the time of speaking. For example, a person says, “I am writing a letter”. It means that he is in the process of writing a letter right now. Such actions which are happening at time of speaking are expressed by present continuous tense. Present Continuous tense is also called Present progressive tense.

Rules. Auxiliary verb “am or is or are” is used in sentence. 1st form of verb or base verb + ing (present participle) is used as main verb in sentence.

Structure of sentence

Positive Sentence
    • Subject + auxiliary verb + main verb-ing (Present participle) + object
    • Subject + am/is/are + (1st form of verb or base verb + ing) + object

If the subject is “I” then auxiliary verb “am” is used after subject in sentence.
If the subject is “He, She, It, singular or proper name” then auxiliary verb “is” is used after subject in sentence.
If subject is “You, They or plural” then auxiliary verb “are” is used after subject in sentence.
The participle “ing” is added to the 1st form of verb i.e. going (go) writing (write)
Examples
        I am playing cricket.
        He is driving a car
        They are reading their lessons.

Negative Sentence
      • Subject + auxiliary verb + not + main verb-ing (Present participle) + object
      • Subject + am/is/are + not + (1st form of verb + ing) + object

Rules for using auxiliary verbs (am or is or are) after subject in negative sentences are same as mentioned above.
Examples.
         I am not playing cricket.
         He is not driving a car
         They are not reading their lessons.

Interrogative Sentences
      • Auxiliary verb + Subject + main verb-ing (Present participle) + object
      • Am/is/are + Subject + (1st form of verb or base verb + ing) + object

For making interrogative sentences, the sentence is started with auxiliary verb rather than putting auxiliary verb inside the sentence. If the subject is “I” the sentence starts with auxiliary verb “am”. If the subject is “He, She, It, singular or proper name” the sentence starts with auxiliary verb “is”. If subject is “You, They or plural” the sentence starts with auxiliary verb “are”.

Examples.
          Am I playing cricket?
          Is he driving a car?
         Are they reading their lessons?

More Examples

Positive Sentences
           I am listening to the news
           You are washing your clothes
           She is riding on horse
           They are playing football.
           It is raining

Negative Sentence
          I am not listening to the news.
          You are not washing your clothes.
          She is not riding on a horse.
          They are not playing football.
          It is not raining.

Interrogative Sentences
         Am I listening to the news?
         Are you washing your clothes?
         Is she riding on a horse?
         Are they playing football?
         Is it raining?

Present Perfect Tense

It is used to expressed an action which happened or completed in past but usually the action which happened or completed at a short time before now (near past) not a very long time before now. Specific time such as two years ago, last week or that day is usually not used in the sentences of in this tense. It means that this tense expresses the action whose time when it happened, is not exactly specified but it sounds to refer to some action that happened or completed in near past.

Rules: Auxiliary verb “has or have” is used in sentence. 3rd form of verb (past participle) is used as main verb in sentence.

Structure of Sentence

Positive Sentence
         • Subject + Auxiliary verb + main verb (past participle) + Subject
         • Subject + has/have + 3rd form of verb or past participle + subject

If the subject is “He, She, It, singular or proper name” then auxiliary verb “has” is used after subject in sentence.
If subject is “You, They or plural” then auxiliary verb “have” is used after subject in sentence.
Examples
       I have eaten meal
       She has learnt a lesson

Negative Sentence
        • Subject + Auxiliary verb + NOT + main verb (past participle) + Subject
        • Subject + has/have + NOT + 3rd form of verb or past participle + subject

Rules for using auxiliary verb “has or have” in negative sentence are same as mentioned above.
Examples
      I have not eaten meal.
      She has not learnt a lesson.

Interrogative Sentences
         • Auxiliary verb + Subject + main verb (past participle) + Subject
         • Has/have + Subject + 3rd form of verb or past participle + subject

Interrogative sentence starts with auxiliary verb. If the subject is “He, She, It, singular or proper name” then the sentence starts with auxiliary verb “has”.
If subject is “You, They or plural” then the sentence starts with auxiliary verb “have”.
Examples
      Have I eaten meal?
      Has she learnt a lesson?

More Examples

Positive Sentences
          They have gone to school.
          They have bought a new car.
          I have started a job
          It has rained.
          The guests have arrived
          John has left for home.
          You have told a lie.

Negative Sentences
        They have not gone to school.
        They have not bought a new car.
        I have not started a job
        It has not rained.
        The guests have not arrived.
        John has not left for home.
        You have not told a lie.

Interrogative Sentences                                                  
       Have they gone to school?
       Have they bought a new car?
       Have I started a job?
       Has it rained?
       Have the guests arrived?
       Has John left for home?
       Have you told a lie?

Present Perfect Continuous tense

It is used to express a continued or ongoing action that started in past and is continued until now. There will be a time reference, such as “since 1980, for three hours etc” from which the action has been started. A sense of time reference is found in these sentences which gives an idea that action has been continued from some time in past till now.  Such time reference or sense of time reference is the identity of Present perfect continuous tense because it tells that action has started from a particular time in past. For example, “He has been reading in this school since 2005”, so the it means that he has started his education in this school in 2005 and he is studying in this school till now.

Note: If there is not time reference or sense of time reference then it is not Present perfect continuous tense because there is no hint about the time of action when it started in past and it seems just an ongoing action at present time which resembles “present Continuous tense. So the reference of time differentiates between Present perfect continuous tense and Present continuous tense.

Rules: An auxiliary verb “has been or have been” is used in sentence. 1st form of verb (base verb) +ing (present participle) is used as main verb in sentence. “Since” or “for” is used before the “time reference” in sentence. If the time reference is exactly known such as 1995, 4 O’clock then “since” is used before the time in sentence. If the time reference is not exactly known such as three hours, six years, four days, then “for” is used before the time in sentence. Time reference such as 3 hours or 5 days is not exactly known because we don’t know that about which three hours a day is told in sentence or about which 5 days in a month is told in sentence. While the 1995 is exactly known time.

Structure of sentence.

Positive Sentence.
• Subject + Auxiliary verb + main verb (Present participle) + Object + Time reference
• Subject + has been/have been + (1st form of verb or base verb + ing) + object +    time reference

If the subject is “He, She, It, singular or proper name” then auxiliary verb “has been” is used after subject in sentence.
If subject is “You, They or plural” then auxiliary verb “have been” is used after subject in sentence.
Examples.
        He has been watering the plants for two hours.
        I have been studying since 3 O’clock

Negative Sentence.
• Subject +”Not” between the Auxiliary verb + main verb (present participle) +     Object + Time reference

• Subject + has not been/have not been + (1st form of verb or base verb + ing) +    object + time reference

To make negative sentence, the word “not” is written between the auxiliary verbs, so it becomes like “has not been or have not been”. The rule for using auxiliary verb “has been or have been” in negative sentences is as same as mentioned above.
Examples.
        He has not been watering the plants for two hours.
        I have not been studying since 3 O’clock.

Interrogative Sentence
• Auxiliary verb + Subject + Auxiliary verb + main verb (present participle) + object +    time reference

• Has/have + Subject + been + (1st form of verb or base verb+ing) + object + time    reference

Interrogative sentence starts with auxiliary verb. If the subject is “He, She, It, singular or proper name” then the sentence starts with auxiliary verb “has” and auxiliary verb “been” is used after subject
If subject is “You, They or plural” then the sentence starts with auxiliary verb “have” and “been” is used after subject.
Examples
      Has he been watering the plants for two hours?
      Have I been studying since 3 O’clock?

More examples

Positive sentences
           It has been raining for three days.
           I have been living in America since 2003.
           He has been playing cricket for two hours.
           They have been watching television since 6 O’clock.
           She has been working in this office since 2007.

Negative sentences
         It has not been raining for three days.
         I have not been living in America since 2003.
         He has not been playing cricket for two hours.
         They have not been watching television since 6 O’clock.
         She has not been working in this office since 2007.

Interrogative sentences
        Has it been raining for three days?
        Have I been living in America since 2003?
        Has he been playing cricket for two hours.
        Have they been watching television since 6 O’clock?
        Has she been working in this office since 2007?