only a stern light
a towing light above the stern light
two towing lights in a vertical line
two white lights in a vertical line
第1题：
A vessel not under command making way at night would show ______.
A.two all-round red lights in a vertical line
B.anchor lights and sidelights
C.two all-round white lights in a vertical line，sidelights and a stern light
D.two all-round red lights in a vertical line，sidelights，and a stern light
第2题：
A vessel towing a barge astern would show，at the stern ______.
A.only a stern light
B.a towing light above the stern light
C.two towing lights in a vertical line
D.two white lights in a vertical line
第3题：
A vessel aground would show the same dayshape as a ______.
A.vessel towing a submerged object
B.dredge underway and dredging
C.hydrographic survey vessel at anchor and surveying
D.None of the above
第4题：
a vessel towing by pushing ahead
a power-driven vessel，not towing
a barge being pushed ahead
either answer A or answer B
第5题：
A towing vessel pushing a barge ahead and rigidly connected in a composite unit shall show the lights of ______．
A.A vessel towing by pushing ahead
B.A power-driven vessel，not towing
C.A barge being pushed ahead
D.Either answer A or answer B
第6题：
A vessel or object being towed astern shall display a(n) ______.
A.forward masthead light
B.after masthead light
C.stern light
D.All of the above
第7题：
A vessel towing astern in an operation which severely restricts the towing vessel and her tow in their ability to change course shall，when making way，exhibit ______.
A.the masthead lights for a towing vessel
B.the lights for a vessel restricted in its ability to maneuver
C.sidelights，stern light and towing light
D.All of the above
第8题：
A tug is best positioned for towing and maneuvering on rivers and other restricted waters where wave action is limited when ______.
A.directly astern and pushing the tow
B.towing on a hawser
C.towing alongside and parallel to the vessel it is towing
D.towing on the hip
第9题：
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 operations
B.Rigid coupled towing
C.Close coupled towing
D.Hard coupled towing
第10题：
increase control of the tow
prevent the towing vessel from going in irons
make the towing vessel less maneuverable
reduce shock stress on the towing hawser