单项选择题
Those ship’s tanks that are particularly important for trimming the ship are the（）.
A.domestics B.settlers C.deeps D.peaks
单项选择题 The words PIPE，BUTT，TUN AND PUNCHEON all refer to（）.
单项选择题 The welds used to join shell plates in flush construction are known as（）.
单项选择题 The welds used to attach stiffeners to a plate are known as（）.
