IXL | Commas with compound and complex sentences

Correct the text by inserting one comma.

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question

Correct the text by inserting one comma.

After NASA successfully landed astronauts on the moon in 1969 the agency made several more missions to the moon in the 1970s.

key idea

In a compound sentence, use a comma before the coordinating conjunction that joins the two independent clauses. Examples of coordinating conjunctions are and, or, but, and so.

We saw a flash of lightning, and seconds later we heard the rumble of thunder.

In a complex sentence, if a dependent (or subordinate) clause comes before an independent (or main) clause, use a comma after the dependent clause. A dependent clause is one that starts with a subordinating conjunction, such as after, although, as, because, before, if, since, unless, until, when, or while.

If she ever gets the chance, Terri would love to visit the Egyptian pyramids.

solution

This is a complex sentence in which a dependent clause comes before an independent clause. You can tell because the first clause starts with a subordinating conjunction, after. Use a comma after the dependent clause.

After NASA successfully landed astronauts on the moon in 1969, the agency made several more missions to the moon in the 1970s.

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Not feeling ready yet? These can help:

FF.9Is the sentence simple, compound, or complex?

TT.5Commas with compound and complex sentences

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