工作中每根钢丝绳都要承受（）、（）、（）、（）等力的作用，使钢丝绳疲劳。
参考答案：拉伸；弯曲；挤压；扭转
In front of the Great Pyramid, Mr Lee stood _____ its great height, and asked many questions.
A．to gaze up at
B．to gaze down at
C．gazing up at
D．gazing down at
病人休克时若补钾，每小时的尿量必须超过（）.
A.10ml
B.20ml
C.30ml
D.40ml
E.50ml
