题型： 单项选择题 难度： 困难
    The?engineer?______my?father?works?is?about?50?years?old.
    A.to whom
    B.on whom
    C.with which
    D.with whom
    答案
    D
    解析
    with whom引导定语从句.with whom放在从句中即为:my father works with the engineer.