军人证件的保管原则?
参考答案:
证件应当随身携带,妥善保管,严禁转借、复制、伪造、涂改,防止遗失和损坏。
—Where is your father?
—He _____ to the Great Wall. He _____ there twice.[ ]
A. went, has been
B. has gone, has been
C. has been, went
D. has gone, went
云、雨、露、霜、雪、雹、雾都是水的“化身”,其中都是固态成分的有______,都是液态成分的有______,有固态、液态等多种成分的是______.