十来岁的年轻人不宜开车.
        Teenagers _____    ______  be______  to drive
 2.如果我是你的话,我就向老师求助.
        If I were you ,____ go to the teacher _____   _____.
3. 我们过去常常在河里游泳.
 We ______   ______     ______ in the river.
4.他为人很随和.
He is very ______    to  ______    ______   ______.
5.Maybe he will go there at once.(改写句子,句意不变.）
________     ______    ______    that he will go there at once.