为什么What is your parents' job?中的parent是复数却不用are而用is?

What letter is a pare of the head?急. What is your plans?还是what are your plans?为什么 What's your name?为什么不是your name is what? what is your name 中为什么用your what are you doing 为什么不说What IS your name? what is your name and address?为什么谓语用is What size is your shirt?还是What is your shirt size?,为什么? Please tell me what your name is中what your name is是补语吗为什么? 为什么 你叫什么名字 翻译为 what is your name 而不是what name is your What is your mother what is your name? What is your brother? What () is your ruler what is your What is your choice? what is your what is your what is your name