A METHOD OF TOWING VESSELS THROUGH POLAR ICE BY MEANS OF ICEBREAKING TUGS WITH A SPECIAL STERN NOTCH SUITED TO RECEIVE AND HOLD THE BOW OF THE VESSEL TO BE TOWED defines ______.A.Towing operationsB.Rigid coupled towingC.Close coupled towingD.Hard coupled

As these features are not all charted，special caution should be exercised ______ vessels navigating in the vicinity．

A.by

B.with

C.on

D.in

The following conditions，except ______，require that vessels be towed through the entire Canal．

A.vessels without mechanical motive power

B.vessels with disabled machinery or bad steering

C.vessels with dangerous cargoes on board

D.vessels liable to become unmanageable for any other reason

此题为判断题(对，错)。

A vessel brought alongside should be fended off the towing vessel by ______.

A.crew members using their arms

B.crew members using the strong muscles of their legs

C.fenders

D.No fending is necessary due to the rugged construction of most towing vessels

There is a ______ when one or more vessels are towing or pushing another vessel or vessels，provided that they are all involved in commercial activities and not in a salvage operation．

A.private safety

B.private maritime adventure

C.common safety

D.common maritime adventure

In ice of higher concentrations ______ is not one of the basic applying rules．

A.keep moving

B.try to work with the ice movement，and not against it

C.excessive speed means ice damage

D.use full astern as often as possible

A、warm

B、heat

C、heaten

D、enheat