In ballasting to survival draft，while in transit，due to extreme wind and wave loads，thrusters or propulsion，if available，should be used to（）.

In towing it is desirable for the tug and the vessel to ride wave crests simultaneously because（）.

Most of your vessel’s superstructure is forward. How will the vessel lie when drifting with no way on?（）.

Besides saving distance along the track line，another advantage of the Scharnow Turn over the Williamson Turn in a man overboard situation because（）.

As a ship moves through the water，it drags with it a body of water called the wake. The ratio of the wake speed to the ship’s speed is called（）.

If a towing vessel and her tow are severely restricted in their ability to change course，they may show lights in addition to their towing identification lights. These additional lights may be shown if the tow is（）.

If a vessel under tow starts jumping on its tow line，the most appropriate action to alleviate the condition is to（）.

Catenary as applied to tow lines denotes the（）.

In towing，heaving lines are used for（）.

Once a towline is connected between the towing vessel and the disabled vessel，the towing vessel should（）.