As we know, a clause is something that has subject and verb. A dependent clause is a clause that does not convey the complete idea or meaning.
Although he was good in mathematics, he could not score Q50 in GMAT.
The above statement contains two clauses
Clause 1 – Although he was good in mathematics
Clause 1 – He could not score Q50 in GMAT
Now let’s look at clause 1, it has subject and verb but it fails to make to convey the complete idea. This is because it contains word ‘Although’. The presence of word ‘Although’ implies that there is some contrasting idea is present and without considering that idea the meaning would not be complete. Hence Clause 1 is a dependent clause. Every sentence must contain at least one independent clause. Hence clause 1 is not a sentence until clause 2 is joined to it.
However, clause 2 is able to convey the complete meaning. Clause 2 states that he could not score Q50 in Quant. It is not dependent on Clause 1; hence it is an independent clause.
An independent clause can be joined with a dependent clause using an only comma.
1) John was not able to reach office on time, as his car met an accident.
2) Even though Mira was well aware of the forest, she got lost in the forest.
CONNECTING TWO INDEPENDENT CLAUSES
In GMAT, there is a strict rule regarding connecting independent clauses together. Two independent clauses cannot be joined together with an only comma (,). They can either be joined with semicolon (;) or they can be joined with using one of the below connectors ->
The above connectors are collectively most commonly known as FANBOYS.
Now let’s see an example to understand the rule thoroughly –
He was good in Mathematics, he cannot score Q50 in GMAT.
The above sentence has two clauses –
Clause 1 – He was good in Mathematics
Clause 2 – He cannot score Q50 in GMAT
Try to answer, whether the above clauses are independent or depended. If you said both are independent clauses, you are absolutely right. As per the rule regarding connective two independent clauses, they must be connected either by a semicolon (;) or one of FANBOYS connector. But in above sentence, both the sentences are connected by only comma. This is not allowed. Hence the above sentence is wrong.
Adding one of FANBOYS connector into the sentence can eliminate this error. While adding the connector, be sure to use the right connector. In above sentence, both clause 1 and clause 2 is presenting a contrasting idea. This contrasting idea should be maintained while selecting the connector. For e.g. If you choose and as a connector, the sentence will not make proper sense. Hence the use of contrasting connector such as Yet or But will be proper in this case.
He was good in Mathematics, but he cannot score Q50 in GMAT.
He was good in Mathematics, yet he cannot score Q50 in GMAT.