联轴节安装调整需要求进行，同心度一般要求控制在（）.
A、0.05mm
B、0.10mm
C、0.15mm
D、0.20mm
参考答案：C
下列检查结果提示肾衰患者进入尿毒症期的是
A．内生肌酐清除率降至20ml/minB．内生肌酐清除率降至30ml/minC．肾小球滤过率降至50ml/minD．血肌酐达到707μmmol/L以上E．血肌酐达到445μmmol/L以上
Look and write. （看一看，写一写）
1. — What are these? — They are _____.
2. — What is this? — It's a _____.
3. — Are they _____? — Yes, they are.
4. — Is this a _____ ? — Yes, _____ _____.
.
.
? — Yes, they are.
? — Yes, _____ _____.