单项选择题
It is NOT advisable to use nylon for alongside towing because it（）.
A.stretches too much B.is too difficult to make fast C.parts too readily D.is too susceptible to mildew
单项选择题 It is good practice to use long towlines for ocean tows because the（）.
单项选择题 In the International Code of Signals，the code signal meaning I require immediate assistance is（）.
单项选择题 In order to pay out or slack a mooring line which is under strain，you should（）.
