By international agreement the boundary of each nation ________ a body of water extends exactly three miles from the coastline.

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In his speech he ________ to the great help the club received from supporters.

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I am not allowed to describe the officers or ________ them by name.

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All the persons ________ are well-know doctors.

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A．referred

B．referred to

C．referring to

D．having been referred to

Many household articles ________ during summer sales at big London stores.

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It is not necessary that your names should ________ your desks.

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In certain parts ________ signs at the roadsides, cameras are forbidden.

[　　]

A．are marked with

B．are marked by

C．marked with

D．marked by

We'd like goods ________ China.

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To save money, we'll use only ________ building materials.

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It would have taken to work the problem out. So I ________ my calculator.

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