进水渠的作用（）
参考答案：
将水流平顺、对称地引向控制段，并具有调整水流的作用
牙骨质来自于
A．牙板 B．牙囊 C．牙 * * D．成釉器 E．上皮根鞘
Before I wanted _______ basketball but I _______ run fast. [ ]
A. play, could not
B. to play, can't
C. play the, can't
D. to play, could not
