下列四幅图反映了地球上南北半球的昼夜情况，阴影表示夜半球，其中日期相同的是
A．①②
B．②④
C．②③
D．③④
答案：B
With the successful launch of Tiangong-l, which was _____ breakthrough in space field,China's space dream took a step closer to _____ reality.
A．a;/
B．the； a
C．a; the
D．the;/
爆破用的爆破器材包括哪两种？
