✍️ English Grammar and Writing · Punctuation
Comma Rules: true or false
Decide fast, then read the reason. Wrong answers are the best teachers, so every statement explains itself.
All statements and answers
Our school has one nurse. In Our school nurse, Ms. Kim, runs the health office. the commas around Ms. Kim are correct, because the name is extra information.
✓ True. The school has only one nurse, so our school nurse already identifies the person. The name is a nonessential appositive, so it gets a pair of commas.
A comma is needed before and in Kai washed the car and mowed the lawn.
✗ False. The word and joins two verbs, washed and mowed, with one subject, Kai. No comma is used.
The rain fell all night, the creek flooded the road. is a comma splice.
✓ True. Both parts are independent clauses and only a comma joins them. Fix it with a period, a semicolon, or a comma plus a word like so.
Writing commas before and after however fixes the comma splice in We finished early, however, nobody left.
✗ False. The word however is not a coordinating conjunction, so the sentence is still a splice. Use a semicolon: We finished early; however, nobody left.
Yet is one of the seven FANBOYS conjunctions.
✓ True. The seven are for, and, nor, but, or, yet, and so.
In The bicycle that has the flat tire is mine. the clause that has the flat tire should be set off with commas.
✗ False. The clause tells which bicycle, so it is essential. Essential clauses, and especially that clauses, take no commas.
The comma after hard is correct in Although the exam was hard, most students passed.
✓ True. Although the exam was hard is an introductory dependent clause, and a comma follows it before the main clause.
Please take a seat Mr. Diaz. needs a comma before Mr. Diaz.
✓ True. The sentence speaks directly to Mr. Diaz, so his name is set off: Please take a seat, Mr. Diaz.
A comma belongs between the subject and the verb in The group of students waiting outside the gym cheered. because the subject is long.
✗ False. A subject never takes a single comma before its verb, however long it is. The sentence is correct with no comma.
The comma in three, tall trees is an error, because three and tall are cumulative adjectives.
✓ True. Tall three trees and three and tall trees both sound wrong, so the adjectives are cumulative. The correct phrase is three tall trees.
A comma follows the state in She grew up in Reno, Nevada, and later moved to Utah.
✓ True. When the sentence continues after a city and state, the state is followed by a comma, just as the city is.
A comma goes between the month and the year in We visited in July 2026.
✗ False. A month and a year alone take no comma: in July 2026. The comma appears when there is also a day: July 9, 2026.
On this site, a comma alone is enough to join two independent clauses when they are closely related in meaning.
✗ False. This site teaches that closeness of meaning does not change the rule: a pair of independent clauses needs a period, a semicolon, or a comma plus a FANBOYS conjunction. (The one exception the lesson gives is a series of three or more short parallel clauses.)