这句话的主语是哪个?

问题描述:

这句话的主语是哪个?
Choosing career is a problem that every youth must be faced.是problem or youth

主语是choosing career (职业选择)
这是个定语从句.职业选择是每个年轻人必须面临的问题.
主句:choosing career is a problem
从句:every youth must be faced the problem
从句修饰宾语“problem”