常用的边坡坡面防护措施有____ 、 ____和工程防护两种。
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沿河路基直接承受水流冲刷,其冲刷防护可分为____和____。
植物防护主要有____、_____、____、三维植被网防护、湿法喷播、客土喷播。
Forty RMB all I can afford to pay for that book today.
A. is
B. are
C. was
D. were
Nobody but Jane ____ the secret.
A. know
B. known
C. have known
D. is known