Tutor profile: Jessica M.

How do I know when I'm using passive voice?

This is an issue I still struggle with! An easy rule of thumb that I recently read: if you can insert "by zombies" into the sentence, it's passive voice. "She was killed by zombies" is passive, whereas "Zombies killed her" is active voice. They are both useful in certain situations, but active voice is generally clearer and more concise. It's easy to fall into the habit of using passive voice, though!

Is carbon dioxide the only issue we have to worry about regarding climate change?

Unfortunately, it isn't. Excess carbon dioxide makes up a large part of the "greenhouse effect" that contributes to climate change, but other gases like methane are actually several times more effective at trapping heat in the atmosphere. Solutions like planting trees to absorb carbon dioxide are wonderful, but we need to approach the problem from many different angles.

How do I know whether to use "who" or "whom"?

This can really be confusing, especially since they are commonly misused. An easy way to remember is to substitute "he" or "him" in the sentence. If you can use "he" in the sentence, then "who" is the correct choice. If you can substitute "him," then you should use "whom." For example: To whom do they speak? They speak to him. See? Him/whom. Easy to remember.