急性胆囊炎时以下哪些情况应尽早手术（）.
A.单纯性胆囊炎
B.化脓性胆囊炎
C.胆囊穿孔
D.有休克先兆
E.寒战、发热
参考答案：B, C, D
—I didn’t know you were a very good cook. Who taught you?
—Here’s a tip If_______rom my mother.
A．took up
B．picked up
C．learned about
D．read about
导料槽中，金属挡板应与皮带保持（）间隙。
A、10mm
B、30mm
C、60mm
D、80mm
