There are two general approaches to attacking a （ ）encryption scheme.The first attack is known as cryptanalysis.Cryptanalytic attacks rely on the nature of the algorithm plus perhaps some knowledge of the general characteristics of the （ ） or even some sample plaintext-ciphertext pairs. This type of （ ） exploits the characteristics of the algorithm to attempt to deduce a specific plaintext or to deduce the key being used. If the attack succeeds in deducing the key, the effect is catastrophic: All future and past messages encrypted with that key are compromised. The second method, known as the （ ）-force attack, is to try every possible key on a piece of （ ） until an intelligible translation into plaintext is obtained. On average, half of all possible keys must be tried to achieve success.

The more he tried to help her, _______ she seemed to appreciate it.( )

（）is entitled to enter into，with a shipper，any agreement，stipulation，condition，reservation or exception as to the responsibility and liability of the carrier or the ship for the loss of or damage to，or in connection with，the custody and care and handling of the goods prior to the loading on，and subsequent to the discharge from，the ship on which the goods are carried by sea.

Although the Shipowner may be responsible for the loss or damage to the goods，his liability may be limited（）the terms of the contract or the statute.

For this part, you need to write an essay expressing your opinion on whether a wall makes it easier or more difficult to be a good neighbor. You should write no fewer than 120 words.　　Please write your composition on the answer sheet.

The network layer provides services to the transport layer. It can be based on either virtual circuits or datagrams. In both cases, its main job is （ ）packets from the source to the destination.

The network layer provides services to the ( ) layer. It can be based on either virtual circuits or datagrams .In both cases, its main job is routing packets from the source to the destination.

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.

Mike: You know, I'm a little uncomfortable with speaking English to foreigners.　　Jane: Why? How're you ever going to become fluent if you don't try to use the language?　　Mike: ______　　Jane: Don't worry. You can become good at English if you learn to be a little more active.

When a tug is pulling on a hawser at right angles to the ship，and the pilot wants to come ahead or astern on the ship’s engine，care must be taken that the pilot（）.

Practice 10　　(1) Advertisement can be thought of “as the making known in order to buy or sell goods or services.” Advertisement aims to increase people’s awareness and arouse interest. It tries to inform and to persuade. (2) There can be no doubt that the growth in advertisement is one of the most striking features of the western world in this century.

On the fully containerized ship，approximately one-third or more of the cargo is on deck above the rolling center. Top stowed containers are subject to（）.