"Mike is kind to Sarah, and his other friends."
or
"Mike is kind to Sarah and his other friends."
Sarah is Mike's best friend.
2 Answers
A comma should not be used in this sentence as "Mike is kind to Sarah" is an independent clause, and "his other friends" is a dependent clause.
When we use a dependent clause to modify the main idea expressed by an independent clause, we link them together, usually with the independent clause coming first and then followed by the dependent clause. In this case, there is no comma separating the two because we do not pause between them in speech.
No comma is needed in your sentence.
Mike is kind to Sarah and his other friends == Mike is kind to Sarah and Tom.
The coordinating conjunction 'and' is linking Sarah and the noun phrase 'his other friends'.
A comma would be needed in the following scenarios:
1.Mike is kind to Sarah, Tom, and his other friends(you could drop the comma after Tom).
2.Mike is kind to Sarah, and his other friends receive similar treatment.
The second sentence is a compound sentence where 'and' conjoins two independent clauses.
You can join any number of clauses like this using coordinating conjunctions and commas:
Mike is kind to Sarah, and his other friends receive similar treatment, but he's still a strange man.
