单项选择题
The square knot is used for（）.
A.forming temporary eyes in lines B.joining two lines of equal size C.keeping line from unlaying or fraying D.joining two lines of different size
单项选择题 The size of wire rope is determined by the（）.
单项选择题 The signal man assisting a crane operator has his arm extended with his fingers closed and thumb pointing upward. This is the signal to（）.
单项选择题 The rope which is the lightest is（）.
