水工建筑物的砂砾石地基是由砂砾石、砂卵石等构成的地基,它的(),因而渗透性强。
A.空隙大
B.空隙小
C.孔隙率高
D.孔隙率低
E.压缩性大
参考答案:A, C
I saw him __ there, __ his clothes and jump into the river.
A.stand; take off
B.standing; take off
C.standing; taking off
D.standing; took off
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