Pls help with simple present & present continuous

Hi pls help me with my homework
Find the mistakes in only five of the sentences.

1. The moon is moving around the earth every 28 days OR
The moon moves around the Earth every 28 days

2. Mark´s wanting to go to laboratory OR
Mark wants to go to the laboratory

3. How many people have study right now? OR
How many people are studying right now?

4. I´m liking your haircut

5. My girlfriend is loving aerobics

6. What is she looking like?

7. They´re understanding what I´m saying very well

8. What is your teacher doing? He´s a plumber too OR
What does your teacher do? He´s a plumber too

1. The moon is moving around the earth every 28 days OR
The moon moves around the Earth every 28 days

2. Mark´s wanting to go to laboratory OR
Mark wants to go to the laboratory

3. How many people have study right now? OR
How many people are studying right now?

4. I´m liking your haircut
This means, I'm just getting used to it, not quite sure, might be all right.
I think you mean to say
I like your haircut.

5. My girlfriend is loving aerobics
No. Try
My girlfriend loves aerobics.

Thanks 4the help Mr.Jlinger :-D

I have another doubt (sorry but is homework so maybe i will have several questions more)

to correct way is to say used to OR use to?

I am used to your face now.
It took some getting used to, but I did it.
I used to think I could only love a beautiful woman.
There is no use to argue about it.
I'll get a bucket. That's something I can use to cover your head.

Well, that's his homework done.
What has he learnt?
Why is, "The moon moves around the Earth every 28 days" correct and not, "The moon is moving around the earth every 28 days"?

Pity the English teacher who gets a shock after a closed book exam that the standard of English of one of her pupils is not what his homework has indicated.

OK, give the right answers...but explain why!

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