1. Uses of Present Simple Tense

We use the Present Simple Tense for the following:

A) To describe things which are always true, or situations that exist now and as far as we know will go on indefinitely; e.g.

i) It takes him ten minutes to go to school.
ii) Trees grow more quickly in summer than in winter.
iii) Ritu dances very beautifully.
iv) Rohan teaches English.
v) Mohan goes to Agra once a month.

B) For habits or things that happen regularly; e.g.

i) I go for a walk daily.
ii) My mother drinks tea every morning.

NOTE-I: However, when we describe repeated actions that are happening around the time of speaking, we use the Present Continuous; e.g.

I’m hearing a lot of good reports about your work these days.

NOTE-II: To describe something that one regularly does at a particular time we can use either the Present Simple Tense or the Present Continuous Tense; e.g.

We usually watch the news on TV at 9.00.
= We are usually watching the news on TV at 9.00.

C) To express a general/universal truth; e.g.

i) The earth revolves round the sun.
ii) Milk is white.
iii) Fortune favours the brave.

D) To talk about thoughts and feelings at the present moment or about immediate reactions to something; e.g.

i) Her mother looks beautiful.
ii) I need some money rightnow.
iii) They both taste the same.

D) To express an exclamation beginning with HERE and THERE. This tells us what is actually happening in the present; means it expresses the present continuous; e.g.

i) Here comes the train!
ii) There he goes!

E) To tell the events of a book, play, film, etc.; e.g.

i) The play begins with a scene of love affairs.
ii) In this film my friend plays the role Akbar.

F) To say quotations from books, notices or very recently received letters; e.g.

i) The books asks to cook very slowly.
ii) What does that notice say?
iii) Hena says in her letter that she is coming to Delhi next week.
iv) Shakespeare says, “Neither a borrower nor a lender be.”
v) A notice at the end of the road warns people not to go any further.

G) To broadcast commentaries of sports events; public functions, etc.; instead of the Past Simple Tense to describe activities in progress where there is stress on the succession of happenings rather than on actual time; e.g.

i) Jadeja runs after the ball, catches it and throws it to the keeper.
ii) When the curtain rises, Juliet is writing at her desk. Suddenly the window opens and a masked man enters.

H) Instead of the present continuous of verbs such as LOVE, SEE, BELIEVE, etc. which cannot be used in the continuous form; e.g.

 I love you. (not I’m loving you.)

Present Simple Tense for future

1. To express future we use the Present Simple Tense when an event is a part of a fixed/regular timetable; e.g.

a) The match starts at 8 a.m.
b) The Mumbai Rajdhani Express leaves at 5 in the evening.
c) When does the shop open?
d) His marriage comes off next Friday.

2. To express future in time and conditional clauses that begin with ‘After, Before, As soon as, As long as, In case, If, Til, Until’; e.g.

a) I shall wait till you finish your lunch.
b) If you don’t work hard, you’ll fail.
c) When you come here, you’ll get a job.
d) Unless you work hard, you will not succeed.
e) He will meet me first as soon as he reaches here.

2. Uses of Present Continuous Tense

We use the Present Continuous Tense for the following:

A) For an action happening at the time of speaking; e.g.

i) My son is reading.
ii) The boys are playing in the garden.

B) For an action happening around this time but not necessarily at the moment of speaking; e.g.

i) I’m writing a book these days.
ii) He is learning French.
iii) The police are talking to a number of people about the murder.

C) To talk about changes, developments, and trends etc.; e.g.

i) The growing number of visitors is damaging the footpaths.
ii) I’m beginning to realize how difficult it is to be a teacher.

Present Continuous Tense for future

1. For already arranged actions which will take place in the near future; e.g.

 I’m going to the cinema tonight.

2. It is also used with ‘Always, Continually, Constantly, Forever, etc.’ to say that something is done repeatedly. Often we do this when we want to show that we are unhappy about it; e.g. 

a) You are always complaining.
b) His son is always playing in the park.
c) My husband is continually complaining of being hard up.
d) He’s forever finding fault with me.
e) They’re constantly having parties until the early hours of the morning.

NOTE: This sort of action quite often annoys the speaker but doesn’t necessarily do so; e.g.

He’s always reading. (It could mean both annoyance and approval of the speaker.)

Compare:

a) Raman is always going away on Sundays. (Continuous tense does not necessarily mean that Raman goes away every Sunday.)
b) Raman always goes away on Sundays. (Simple tense means Raman goes away every Sunday.)

3. Uses of Present Perfect Tense

A) For a recently completed activity. We normally use JUST in such a case; e.g.

i) He has just gone out. (Means he went out a few minutes ago.)
ii) Has he just gone out? (not ‘Did he just go out?’)
iii) Reema has posted the letter.

NOTE: The word JUST must be placed between the helping and the main verb if this word is to be used.

B) To express past actions whose time is not given and is not definite; e.g.

i) Have you read my book on English literature?
ii) Have you had breakfast?
iii) I have never known him to be angry.
iv) Sohan has been to England.

Compare:

1-a) I have read the instructions. (The time is not given; so the perfect tense)
b) I read the instructions last night. (time given; so simple past)

2. Did you have breakfast at the hotel? (Here, though time is not given, use of Past Simple Tense is not wrong. The tense is simple past you see, so it does mean the time is understood.)

3-a) Rohan Gupta has written a number of stories. (It implies that Rohan Gupta is still alive and can write more.)
b) Rohan Gupta wrote a number of short stories. (It implies that Rohan Gupta is dead now presumably.)

C) To describe past events when we think more of their effect in the present than of the action itself; e.g.

i) Sohan has drunk all milk. (present effect: means there isn’t left more milk.)
ii) She has cut her hand. (present effect: means it’s bleeding now.)
iii) The lift has broken down. (present effect: means we have to use the stairs.)
iv) I’ve washed my bike. (present effect: means it looks lovely now.)

NOTE: But actions expressed by the simple past without a time expression do not normally have results in the present.

D) To talk about how long an existing situation has lasted, even if we don’t give a precise length of time; e.g.

i) Prices have fallen sharply over the past five months.
ii) They’ve grown such a lot since we last saw them.
iii) We’ve recently started to walk to work instead of taking the bus.

E) To denote an action beginning at some time in the past and continuing up to the present moment. It’s often done with SINCE or FOR; e.g.

i) Jhanvi has worked here since 2004.
ii) Ram and Shyam have lived here for 2 years.
iii) Has he written since he left? [SINCE+CLAUSE]
iv I have smoked since I left school.

NOTE-I: In this situation we can also use the Present Perfect Continuous Tense; e.g.

Jhanvi has been working here since 2004.

NOTE-II: FOR is used for period of time. FOR can also be used with the Past Simple Tense, but when it denotes a terminated period of time; e.g.

We lived there for ten years. (means we do not live there now. )

But in the present perfect tense it denotes a period of time extending into the present; e.g.

We have lived there for ten years. (means we are still living there). SINCE is used with a point in time and means ‘from that point to the time of speaking.

NOTE-III: In a sentence having SINCE-CLAUSE , the SINCE-CLAUSE generally is in the Past Simple Tense, and the main clause is in the present perfect; e.g.

a) I haven’t been able to play tennis since I broke my arm.
b) She may have got a job by now since I last saw her.
c) Since I last met him, he must have been married.

However, we can use a present perfect in the SINCE-CLAUSE also if the two situations extend until the present; e.g.

Since I’ve lived here, I haven’t seen her.

NOTE-IV: Note that there is difference between LAST and THA LAST. Last week = a point in time about seven days ago. The last week = the period of seven days just completed. So, we use SINCE before LAST; and FOR before THE LAST; e.g.

a) I have been here since last week.
b) I have been here for the last week.

NOTE-V: SINCE+CLAUSE is also possible; e.g.

I have worked here since I left school.

NOTE-VI: The adverb EVER SINCE with the Present Perfect Tense is also possible; e.g.

He had a bad fall last year and has been off work ever since.

F) LATELY, RECENTLY used with the Present Perfect Tense also indicate an incomplete period of time; e.g.

He hasn’t been here lately/recently. (here LATELY/RECENTLY = at any time during the last week/month, etc.)

NOTE-I: In affirmative sentences RECENTLY = at some undefined time during the last week/month, etc.); e.g.

a) He has been here recently.
b) There have been some changes recently. (RECENTLY = at some undefined time during the last week/month; etc.)

NOTE-II: But when we use it with the Past Simple Tense, RECENTLY = a short time ago; e.g. 

He left recently. = He left a short time ago.

G) The Present Perfect Tense is never used with adverbs of past time such as YESTERDAY, AGO, etc.; e.g.

INCORRECT: My brother has gone to Mumbai yesterday.
CORRECT:  My brother went to Mumbai yesterday.

4. Uses of Present Perfect Continuous Tense

A) For an action which began at some time in the past and is still continuing. Sometimes we use this tense with expressions indicating the time period SINCE and FOR; e.g.

i) He has been sleeping for an hour.
ii) They have been playing since five o’clock.
iii) She has been living in Delhi for ten years.
iv) People have been saying for ages that the building be/should be pulled down.

NOTE: Without such a time expression, the Present Perfect Continuous Tense refers to a recent situation or a recently completed activity, means it has ended e.g.

a) He has been having a tooth out.
b) I have been thinking it over.
c) It has been snowing.

B) We often use the Present Perfect Continuous Tense when we ask a question with HOW LONG, and when we say how long something has been in progress; e.g.

How long have you been playing cricket?

Comparison between the Present Perfect Tense and Present Perfect Continuous Tense

An action which began in the past and is still continuing or has only just finished can be expressed by either the present perfect or the present perfect continuous, but only with certain verbs. Those verbs are EXPECT, HOPE, BELIEVE,  LEARN, LIE, LOOK, RAIN, SLEEP, SIT, SNOW, STAND, STUDY, TEACH, WAIT, WANT, WORK; e.g.

How long have you learnt English?
= How long have you been learning English?

He has studied for two hours.
= He has been studying for two hours.

NOTE: The Present Perfect Continuous Tense can also be used without FOR or SINCE.