Possessive case is generally used with living things e.g. the governor’s bodyguard.

But is also used with personified objects:

2.  Comparison of adjectives:

e.g.

2) In comparing two things or classes of things the comparative should be used; as, Of Mumbai and Madras the former is wealthier.

Of two evils, choose the less (not least).

Note:  later and latest refer to time, latter and last refer to position. Elder and eldest are used only of person, not of animals or thing. Older and oldest are used of both persons and things.

3. Personal pronouns

i.e the construction is- “you and I” not “I and you” ,”you and he” not “he and you”  ,”he and I” not “I and he”    

4. Mood

Subjunctive mood:

a. past subjunctive is used

1) After the verb wish to indicate a situation which is unreal or contrary to fact: as,

2) After if, to express improbability or unreality in the present: as;

3) After as if/though, to indicate unreality or improbability: as,

5. Tense

This is a very vital part in grammar & also for apti.

6. Agreement of the verb with the subject

1) If the singular subjects are preceded by each and every the verb usually singular:as’

2) Two or more singular subjects connected by or, nor, either….or, neither...Nor take a verb in the singular: as,

3) When subjects joined by or,nor are of different numbers, the verb must be plural, and the plural subject must be placed next the verb ;as,

Rama and his brothers have done this.

4) When the subjects joined by  or or nor are of different persons,the verb agrees with the nearer ; as,

5) Either, neither, each, everyone, many a, must be followed by a singular verb; as,

6) Words joined to a singular subject by ‘with’, ‘together with’, ‘in addition to’, or ‘as well as’, etc.,are parenthetical, and therefore do not affect the number of the verb ; as,

7. The participle

a. Present participle

We met a girl carrying a basket of flowers.

b. Past participle

Driven by hunger, he stole a piece of bread.

c. Perfect participle

1) Since the participle is a verb-adjective it must be attached to some noun or pronoun ; in other words it must always have a proper ‘subject of reference’.

The following sentences are incorrect:

8. The gerund

9. Auxiliaries

This is another important chapter in grammar.

10. Position of adverbs

11. Preposition

1) Since is used before a noun or phrase denoting some point of time, and is preceded by a verb in the perfect tenses ;as,

2) From is used with non-perfect tenses; as,

3) For is used with a period of time; as,

He has been ill for 5 days.

4) In before a noun denoting a period of time, means at the end of; within means before the end of; as,

5) Beside means by the side of, while besides means in addition to.

6) The prepositions for, from, in, on are often omitted before nouns of place or time; as,

We did it last week, I can’t walk a yard, wait a minute.

7) In and at are used in speaking of things at rest; to and into are used in speaking of things in motion; as,

8) On is used in speaking of things at rest, and upon the things in motion; as,

9) Till is used of time, and to is used of place; as,

I slept till eight o’clock.            , He walked to the end of the street.

10) With often denotes the instrument and by the agent; as,

11) But- as a rule is a conjunction. When used as a preposition but means “except”, “with the exception of”; as,

Note: also take a look at the prepositions that shows some most common relation to some words; as,

1) Place:

Went about the world, leaned against a wall, tour round the world, put pen to paper, stand without the gate.

(2) Time: by three o’clock, ten minutes to twelve, on Monday.

(3) Agency, instrumentality:

Sent the parcel by post, was destroyed by fire, heard this through a friend, cut it with a knife.

(4) Manner: fought with courage, won with ease.

(5) Cause, reason, purpose:

Died of fever, died from fatigue, concealed it through shame, took medicine for cold.

6) Possession:

The mosque of Omar, the boy with red hair

7) Contrast, concession:

For (in spite of) all his wealth he is not content, with (in spite of) all his faults I admire him. 

12. Conjunctions and their uses

1) Since, when used as a conjunction, should be preceded by a verb in the present perfect tense, and followed by a verb in the past indefinite tense; as,

I have been in such a pickle since I saw you last.

2) That is now used

a. To express reason, cause and is equivalent to because, for that, in that; as,

b. To express purpose and is equivalent to in order that; as,

We sow that we may reap.

C. To express consequences, result, effect; as,

I’m so tired that I can’t go on.

3) Scarcely should be followed by when, and not by than.

Scarcely had he gone, when (not than) a policeman knocked at the door.

4) No sooner is followed by then, and not by but.

13. Noun and pronoun

Let you and me (not I) do it.

14. Adjectives

1) A very common form of error is exemplified in the following sentence:

15. Articles

1) Before a word beginning with a consonant sound a is used; as,

3) The red and white rose. (Means one rose)

16. Structures

1) subject+verb+noun/pronoun+adjective:

2) Subject+verb+noun/pronoun+present participle:

3) Subject+verb+noun/pronoun+plain infinitive:

4) Subject+verb+noun/pronoun+past participle:

5) Subject+verb+noun/pronoun+ (to be +) complement:

6) It+be+no good.e etc. +gerundial phrase:

7)      If clause                                                                                             main clause

     (Simple present)                                                                     (Will/shall/can/may+plain infinitive)

If you study hard                                                                                      you will get a first class.

If he runs all the time                                                                             he can get there in time.

Note: Conditionals of this type tell us that something will happen if a certain condition is fulfilled. The condition may or may not be fulfilled.

(8)           If clause                                                                                   main clause

         (Past subjunctive)                                                  (Would/should/could/might+plain infinitive)

If you studied hard                                                                                 you would get a first class.

If we started now                                                                                     we would be in time.

Note: Conditionals of this type are used when we talk about something which we don’t expect to happen or which is purely imaginary.

(9)           If clause                                                                                         main clause

              (Past perfect)                                                         (Would/should/could/might+perfect infinitive)

If you studied hard                                                                            you would have got a first class.

If he had taken my advice                                                           he would not have got into trouble.

Note: Conditionals of this type say that something did not happen becoz a certain condition was not fulfilled.

17. The sequence of tenses:

1) A past tense in the principle clause is followed by a past tense in the subordinate clause;as,

She replied that she felt better.

I found out that he was guilty.

Note: there are however two exceptions to the above rule:

(b)  When the subordinate clause is introduced by than, even if there is a past tense in the principle clause it may be followed by any tense required by the sense in the subordinate clause ;as,

2) A present or future tense in the principle clause may be followed by any tense required by the sense; as,

18. Few sentence construction:

1)  (a) He thought that he was safe there.

     (b) He thought himself to be safe there.

2)   (a) I believed that he was a true friend.

      (b) I believed him to be a true friend.

3)   (a) This proved that the man had stolen the horse.

      (b) This proved the man t have stolen the horse.

(4)  (a)  We know that Rama is alive.

      (b) We know Rama to be alive.

19. In such sentences as the following, but is equivalent to a relative pronoun followed by not, and serves to introduce an adjective clause:-

(1) There was not a woman present but wept to hear such news. [That is, who did not weep to hear such news.](2) There is no fireside but has one vacant chair. [That has not one vacant chair.]

So, this was a brief review of few important grammatical rules. Follow a good English grammar book to learn about English grammar more effectively, efficiently.

Best Wishes.