I don't know how they deal with the problem=I don't know （ ） they（ ） （ ）the problem

I don't know how they deal with the problem=I don't know （what ） they（do ） （with ）the problemhow 后面用deal withwhat 后面用do with 这是固定用法 希望能帮到你,祝更上一层楼O(∩_∩)O有不明白的请继...