Michael____to swim in West Lake yesterday. [ ]
A. see
B. was seeing
C. was seen
答案:C
如果在你的生活中遇到下列情景,请说出你的正确做法。
氮洗分子筛的吸附过程是()。
A.物理吸附
B.化学吸附
C.理想吸附
D.多种吸附并存