1. What color eyes does he have?

He has dark brown eyes.

2. What color hair does the dog have?
She has brown hair.

3. Hair is used not only for people's hair but also for animals' fur.

4. The order of writing the date in English is different from that in Korean.

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Are the expressions above correct?
If there are any errors, let me know them, please.

3 answers

All look good although "fur" is usually used when referring to animals; "hair" is for humans.

All punctuation is correct.
Thank you for your answer.
What about the follwoing questions and answers? Are they also correct?

1. What is the color of Mike's eyes?
It is blue.

2. What is the color of the dog's fur?
It is brown.
1. What is the color of Mike's eyes?
They are blue.

2. OK as is.