How old are they?

how Adverb

— The word "how" is a question word, to ask about the way something happens or the way people do things. How will we ever solve this problem? — The word "how" is used to tell about the way something happens or the way people do things. I know how we can solve this problem? This is how to make this machine work. — used to show that you feel strongly about something. How old he looks!

how Subordinator

— You use how to tell that something happens, is done, or is true. She told him how it wasn't fun anymore.

old Adjective

— If someone or something is old, they are not young; they have been in existence for a long time. An old man has gray hair. — How old someone is, is their age. "Ashley, how old are you?" "I'm only 16 years old."

are Verb

— Are is the present tense, second person form of the verb be. Hello John, how are you? We are all happy. Are we there yet? John and Mary are playing. Are you all hungry?

they Pronoun

— "They" is used to talk about two or more people, not you or the person you are speaking to. I love Josie and Reg. They are nice people. — "They" is used to talk about two or more things. Can you get the books for me? Theyre over there. — "They" is used to talk about one or more person when you don't know the sex or number. If a person is fast, they can get there early. — "They" is used to talk about people in general. When are they going to finish that new building? They say you should drink eight glasses of water a day.