My uncle goes to the dentist's once a month.划线部分提问

问题描述:

My uncle goes to the dentist's once a month.划线部分提问
划线部分是once

应该是:
How many time does your uncle go to the dentist's a month?
你叔叔一月去看牙医几次?
once 一次 ,对次数提问用how many times