化油器浮子破裂，会导致燃料供给系（）。
A.混合气过浓
B.混合气过稀
C.来油不畅
D.怠速不良
参考答案：A
I had hoped to see her off at the station, but I _____ too busy.
A．was
B．had been
C．would be
D．would have been
血细胞显微镜计数的技术误差通常包括（）。
A.微量吸管未经校正
B.采血操作不当
C.稀释倍数不准
D.充液不当
E.计数域误差
