"How old is he?"
来源：这是一种常见的问年龄的句式。
例句: "How old is your brother?"（你哥哥多大了？）
"What is his age?"
来源：这是另一种常见的问年龄的句式。
例句: "What is the age of the new employee?"（新员工的年龄是多少？）
"Can you tell me his age?"
来源：这是一种礼貌的问年龄的句式。
例句: "Can you tell me how old your daughter is?"（你能告诉我你女儿多大了吗？）