they usually make a birthday cake for my birthday?(对划线部分提问)

问题描述:

they usually make a birthday cake for my birthday?(对划线部分提问)

划线的是a birthday cake吗?如果是的话,可以提问:what do they usually make for your birthday?
如果划线的是make a birthday cake,则提问:what do they usually do for your birthday?

What do they usually do for your birthday ?

What do they usually do for your birthday? (划线是: make a birthday cake )