船舶驶入浅水区，其船速下降的原因是______。
A. 船体下沉，纵倾增大
B. 兴波增强
C. 推进器效率下降
D. 以上都是
In a weather report，POSITION GOOD means that the position is______．
A. a good one
B. reliable
C. is easy to be fixed
D. Obtainable
Chafing gear(防摩擦装置) is used to______．
A. anchor the boat
B. pick up heavy loads
C. protect fiber rope from abrasion
D. strengthen mooring lines
In midocean，the characteristics of a wave are determined by three factors．What is NOT one
A. Effect of the moon’s gravity
B. Fetch
C. Wind velocity
D. Length of time a wind has been blowing
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