No,they do not utilize O2.They utilize CO2.

Utilize is a verb.

We talked about how to best utilize the extra bedroom in our home.

How will you utilize the extra space in the basement?

How can our school best utilize the grant money?

"Utilize your pencil and write down the answer!" Is one way to utilize the word "utilize". Also, using the word "Use" or "Using" is a better word than "Utilize".Utilize means "to make use of", so you could say: "During the SATs, I utilize my time well by double-checking my answers."

Sure! Here's a sentence using the word "utilize": "Employees are encouraged to utilize the new software to improve efficiency in the workplace."