实验室最常见的滴定管有（）和（）。
参考答案：酸式、碱式
The farm as well as its neighboring hills we once spent so much time ___ a new look recently.
A．on has taken
B．has taken
C．on having taking
D．having taken
下列哪些体征属于脑膜刺激征（）
A.霍夫曼征
B.克尼格征
C.戈尔登征
D.奥本汉姆征
E.卡达克征
