In most instances, place a comma between two sentences that are joined with a coordinating conjunction--and, but, or, for, nor, so, yet:1. She was not sure if she had the necessary mathematical abilities to be an engineer, so she pursued a graduate degree in history.
2. He was surrounded by fifty people, yet he felt all alone.
You do not need to place a comma between two independent clauses if they are short and similar in meaning, provided that no misunderstanding will take place, as illustrated in the following example:
1. Some doctors advertise their services but many doctors find this reprehensible.
2. The absence of the comma in this sentence is acceptable; it is not necessary to prevent misreading.
Other comma resources:1. Use a Comma After Conjunctive Adverbs and Transitional Phrases at the Beginnings of Sentences
2. Use Commas After Introductory Subordinate Clauses
3. Use Commas Around Nonrestrictive Parenthetical Elements
4. Use Commas Before Nonrestrictive Adverbial Phrases or Clauses at the Ends of Sentences
5. Use Commas to Separate Adjacent Parallel Elements
AjiteshArun :
My concern is the sentence query in blue text.
It says we can join two ICs only by FANBOYS. Can we do this on the GMAT?