Add a Comma to Each Sentence That Needs One

question 16

Short Answer

Add a comma to each sentence that needs one. Some sentences do not need a comma.
-Before I was adopted my parents tried desperately to have a baby.

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Definitions:

Nitrous Oxide

A colorless, non-flammable gas with a slight sweet odor, used as an anesthetic and in the production of rocket motors and semiconductors.

Invertebrates

Animals that lack a vertebral column, or backbone, including species such as insects, molluscs, and crustaceans.

Natural Resources

Materials or substances occurring in nature which can be exploited for economic gain, such as minerals, forests, water, and fertile land.