In grammar, conjunction is a part of speech that connects words, phrases and clauses that are called conjuncts of the conjunction.
1. Co-relative Conjunctions
They are double conjunctions and they come together in the sentence. No part can be replaced by any other word of similar meaning.
- No sooner - than, Scarcely / Hardly - when
As their first part comes before the beginning of the sentence, the sentence will have inversion i.e., auxiliary verb coming before the subject. Then, it must be noticed that 'than' comes with 'no sooner' and 'when' with scarcely / hardly.
Hardly he stood to deliver his speech when there was a pandemonium. (did he stand)
No sooner did he start writing when his pen ran out of ink. (than)
- Not only - but also
With this conjunction there occurs the error of position. The part of speech which comes after 'but also', the same part of speech should come after 'not only' also. Here, important part is that the position of 'not only' should be guided or correct according to the position of 'but' also, and not the vice-versa. While 'not only' must be used together, 'but also' can be used separated. Then, the position of 'but' will be deciding the things.
In the scuffle I not only lost my purse but my gold watch also.
Here, after 'but' a noun has come. Naturally, after 'not only' also a noun should be there. Place 'not only' after 'lost' and the sentence is correct.
- Both - and
With these two lines are involved. First, the error of position like the previous rule and Second, 'both - and' is not used in negative sentence. It must also be had in mind that 'and' cannot be replaced by 'as well as'.
He is supposed to be a scholar as he has studied in America and India.
Place 'both' after 'in' to correct the error of position.
- So - that
'So' is an intensifier and as a conjunction takes 'that' with it.
- Such - as / that
'Such' acts both as an intensifier and a qualifier. When 'such' comes at beginning of a sentence and after it a verb comes then it takes 'that' with it. 'That' is used also when 'such' shows the intensity of feeling. 'As' is used with 'such' when it comes in the middle of the sentence and does not show the intensity.
There is no such boy that you are looking for. (as)
Such was his anger as every attempt to pacify him failed. (that)
He was in such an emotional frenzy as he listened to none. (that)
- Though / Although - yet
With 'though' or 'although' either 'yet' or simply a comma is used before the next sentence, not 'but'.
Though the meeting started late but all the members were present. (yet or comma(,))
- The reason why
The reason is used erroneously in the sentence thus -
The reason why he spoke so rudely is because he is emotionally disturbed today. (X)
As 'reason' itself denotes a cause using 'because' in the sentence is wrong. The reason sentence does not take 'because'. 'Why' is applicable in the sentence though it may not be there also.
The reason why he spoke so rudely is (that) he is emotionally disturbed today.
2. Independent Conjunction
In this group there are conjunction which are alone but with them some rules are involved.
- Since
As a time conjunction, 'since' combines two sentences where the sentence coming before 'since' is in present perfect and the sentence after 'since' is in past indefinite.
Nothing has changed in this town since I have left it.
(Remove 'have left' and use 'left')
- In case / Provided
Both denote condition. 'In case' means 'in the condition' and 'provided' means 'on the condition'. After them neither will not shall nor any modal auxiliary is used.
India will become a developed country provided it will strengthen its infrastructure. (Strengthens)
I shall remain indoors provided it rains continuously. (In case)
- Lest
With 'lest' (meaning 'for fear that') as conjunction the following sentence takes only 'should' (without 'not') as auxiliary verb.
You must take judicious decision lest you may commit error. ('Should' in place of 'may')
- Whether
As a conjunction 'whether' is used when (i) 'doubt' verb is used in the sentence or (ii) the sentence shows any doubt. Often with 'whether' 'or not' / 'or no' is used.
I was unable to decide that to leave that question or attempt it. ('Whether' in place of 'that')
The entire country doubts that India will win the world cup. (Whether)
- Supposing
'Supposing' itself showing condition does not take 'if' with it.
- If / Unless
'Unless' means 'if not' and hence 'not' is not use in the sentence containing 'unless'.
Success is very doubtful unless you will not persevere in your effort. (x)
'Not' will be removed and since 'unless' is also a conditional word 'will' is inapplicable here.
Success is very doubtful unless you persevere in your effort.
- Till / Until
'Till' and 'Until' being time conjunction do not take will, shall or any modal auxiliary. 'Till' denotes period of time and 'until' denotes point of time. After 'until' 'not' is not used.
Until government does not make effort to improve the condition of the poor, how will it improve ? (Use 'makes' in place of 'does not make')
The condition looked up until a communist government rules the U.S.S.R. (till)
- When / While
'When' is used with a sentence that denotes the completion of a work and the point when another action takes place.
When he had spoken people went home.
'While' is used with a sentence that denotes the continuation of a work and the point of time when another action takes place.
Showing continuation, 'while' not 'when' will be correct if the sentence is in continuous tense.
When the match was going on, one part of the stadium collapsed. (While)
- Like / As
Both have the same meaning but 'like' is a preposition and thus after it word or group of words will come not a sentence, whereas 'as' is a conjunction and after it a sentence will follow.
Like the expert committee recommended, the government is making a three-tier system. (As)
- Nothing else
'Nothing else' takes 'but' after it.
It is nothing else except pride that leads to one's downfall. (But)
- Other
'Other' takes 'than' after it.
India has no other claim in this race of development but her quality human resource. ('than' in place of 'but').