Because pets give us strength and pets are very cute!
Their tails are very long.
->Why do you put s behind tail?
Hi, Minju! Thank you for this. I agree, pets are really cute. They help us releive stress. Let's talk again soon. See you!
--Teacher Anji
Because pets give us strength, and pets are very cute!
>> CORRECT
Their tails are very long.
->Why do you put s behind tail?
Answer: "tail" here is used as noun, and the subject "Their" is plural, so we need to use the plural form, too.