单项选择题
The conclusion is（）the said ship is fit to continue to sail.
A.it B.this C.that D.what
单项选择题 The burden of proving unseaworthiness is upon those who（）it.
单项选择题 The bottom of the mast rests on a part of the keel called the mast（）.
单项选择题 The boom stops are installed on an offshore crane to（）.
