A conjunction is defined as a word which either joins two sentences or two words together. Not only are they used to join sentences together, they are also used to make them more compact. For example, "John and Dave are playing." This sentence is a shorter way of saying, "John is playing and Dave is playing." Similarly, "Darren is handsome but short" is a shorter way of saying "Darren is handsome but he is short." In some cases, a conjunction is used only to join two words. For example, "Susan and Cindy are friends." This sentence cannot be divided into two different sentences. Depending on their functions, conjunctions are divided into four major types:

• Coordinating Conjunctions
• Subordinating Conjunctions
• Correlative Conjunctions
• Compound Conjunctions

When the two sentences joined together by the conjunction are of equal rank or importance, i.e., if it contains two independent statements, then the conjunction is called a coordinating conjunction. It is defined as a conjunction that joins together clauses of equal rank. The main coordinating conjunctions are and, but, for, or, nor, also, either ... or, neither ... nor. There are four types of coordinating conjunctions. (I) Cumulative or Copulative These conjunctions add one statement to another. » I am not working, and I do not wish to work. (II) Adversative This type of conjunction expresses opposition or contrast between two statements. » He was in a hurry but he had to take it slow. » I wanted to talk but I kept quiet. » I would have married you if I were single. (III) Disjunctive or Alternative These conjunctions express a choice between two alternatives. » She must weep, or she will die. » He should eat, or he might faint. » Neither a borrower, nor a lender be. (IV) Illative This type of conjunction expresses an inference. » Someone certainly fired, for I heard a gunshot. In the sentence, "I wore the red dress, because it is my favorite", the clause 'because it is my favorite' is dependent on the main clause 'I wore the red dress', thus indicating that it is a dependent or subordinate clause. Thus, the conjunction introducing the subordinate clause is called a subordinating conjunction. A subordinating conjunction is defined as a conjunction that joins a clause to the one that it is dependent on (for its complete meaning). Subordinating conjunctions include after, because, if, that, though, although, till, before, unless, as, when, where, while, than, why, until, unless. Examples: » He is better at singing than you are. » She won't pay unless asked to. » Tell the teacher that I am unwell. » I left you a message since you did not answer. Subordinating conjunctions can be classified according to their meaning. (I) Time » Wait here until mother gets back. » I will get there before you do. » Rita left after he was gone. » Things have changed since we last met. (II) Cause or Reason » My brother couldn't attend the wedding because he was sick. » Mary could not make it to the party since she was busy. » We'll go shopping some other time as I have to be at work today. (III) Purpose » I had to hold him so that he wouldn't fall. (IV) Result or Consequence » He was so weak that he could barely stand. (V) Condition » I will dance if my friend does. (VI) Concession » Though he wants me killed, yet I will meet him. (VII) Comparison » Edward is stronger than Emily. » A banana tastes better than an apple. Sometimes, conjunctions can be used in pairs as follows:

• Either ... or » Either sit here or there.
• Neither ... nor » Neither me nor Peter liked her.
• Both ... and » Both Nancy and Sarah love shopping.
• Though ... yet » Though he was late, yet he didn't apologize.
• Whether ... or » Whether you come or not, is completely your choice.
• Not only ... but also » Not only is Sarah beautiful, but also very intelligent.

Such conjunctions are called correlative conjunctions or simply correlatives. When more than one word are used as conjunctions, they are called compound conjunctions. These include:

• in order to » I have to meet you in order to know you better.
• on condition that » I will let you go on condition that you will be back in time.
• even if » I will go even if I don't want to.
• so that » Mr. Johnson gave him some money so that he could feed himself.
• provided that » You can borrow my dress provided that you don't spoil it.
• as though » He acts as though he knows it all.
• as well as » Susan has been to Italy as well as Spain.
• as soon as » I got here as soon as I could.
• as if » You behave as if you care.

Certain words are used as both prepositions and conjunctions. In the sentence, "I have not met him since Monday", 'since' is used as preposition. On the other hand, in "We will go shopping tomorrow, since you want to", 'since' has been used as a conjunction. It may take a while to learn how to distinguish between the two. The same can be easily learned by solving various exercises.