合同当事人互负债务,先后履行顺序已有约定,后履行义务的当事人可在先履行义务的当事人未履行之前或履行有暇疵时,拒绝对方的履行请求,合同法称此为( )

（）shall be liable for loss of and damage to the Vessel and／or goods arising or resulting from inaccuracies in stating the description，quantity，weight，measurement or contents.

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

When loading or discharging dry mud or cement，crew members should use goggles and（）.

Effects which are dutiable or subject to prohibitions or restrictions should be declared in （）.

依据我国《合同法》的规定，在双务合同中，当事人互负债务，合同约定有先后履行顺序的，负有先履行义务的一方当事人（）其债务。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。