防隔水煤柱是指为保护矿井安全，在矿井或采区设计时（）的煤柱。
A、开采
B、留设
C、保护
参考答案：B
用画线单词的对应词填空。
1.This T-shirt is white. That one is _____.
2.My ruler is long. His ruler is _____.
3.Please _____here, Jeff. Don't go there(那里)。
4.They sell these shorts for only ￥2. Mary _____ some shoes.
5.This big sweater is ￥12 dollars. That _____sweater is only 5 dollars.
心房颤动的患者，体格检查时可出现
A．奇脉
B．重搏脉
C．交替脉
D．水冲脉
E．短绌脉
