次贷危机是起源于美国的、因次级抵押贷款机构破产、投资基金被迫关闭、股市剧烈震荡引起的风暴。 ( )
参考答案：对
In 1969, Neil Armstrong, an American astronaut, _____ the moon for the first time, which announced
man began to march at the universe.
[ ]
A. walked
B. climbed
C. set foot in
D. set foot on
如何穿、脱防毒服？
