Before welding can be done in a tank that has carried petroleum products，a certificate must be obtained from（）.

In order to withstand fluid head pressure on a ship，stiffeners are often attached to the bulkhead（）.

The bottom of the mast rests on a part of the keel called the mast（）.

The burden of proving unseaworthiness is upon those who（）it.

I saw the cargo surveyor（）the cargo on deck just a minute ago．

The smallest size of flaw that can be detected on a radiograph examination of a weld will be indicated by the（）.

Prior to burning or welding on a fuel tank on a ship，regulations require that an inspection be made. An entry in the unofficial logbook is required if this inspection is made by（）.

The end of the joint with the exterior threads is called the（）.

The lines led forward from the bow and aft from the stern when a vessel is moored to the dock are（）.

Let’s submit the case（） the cargo surveyor.