题干
The opening day of Expo 2010 Shanghai Chi
na we have been forward looking to_____ to arrive.
na we have been forward looking to_____ to arrive.
A：being
B：be
C：i
D：will
答案(点此获取答案解析）
C
2Z的影响示意图，图中纵坐标表示平衡混合气体中Z的体积分数。下列叙述正确的是
