对于堤身透水性强，在反滤料源丰富以及堤身断面较小或堤土过于稀软不宜做（）时，可采用反滤层法抢护。
参考答案：导渗沟
He has to ask for a loan because all his savings had been ______. [ ]
A. cleaned up
B. used up
C. giving out
D. run out
斜巷提升的“三固定”指固定绞车工、固定信号工、（）、“四保险”指保险档、保险杠、保险绳、保险网。
