单项选择题
A block that can be opened at the hook or shackle end to receive a bight of the line is a（）.
A.bight block B.gin block C.heel block D.snatch block
单项选择题 You can safely step in the bight of a line（）.
单项选择题 When a pilot is on board to pilot the vessel the Letter（）must be hoisted.
