安全生产许可证的有效期为()年。
A.2
B.3
C.4
D.5
参考答案:B
She ________ his number in the phone book to make sure that she had got it right.
A.looked up
B.looked for
C.picked put
D.picked up
今年5月1日,我国海军舰艇编队开始了人民海军历史上的首次环球航行,总航程约3万海里。请问这次航行是丛我国哪个军港出发的?()
A、大连港
B、青岛港
C、上海港
D、旅顺港