Mark the letter A, B, C or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

The production of different kinds of artificial materials are essential to the conservation of our natural resources

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions from 33 to 51.

John lost the ___________ bicycle he bought last week and his parents were very angry with him because of his carelessness

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions from 33 to 51.

If it ___________ more humid in the desert of the Southwest, the hot temperatures would be unbearable

Mark the letter A, B, C or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

The purpose of the United Nations, broad speaking, is to maintain peace and security and to encourage respect for human rights

Mark the letter A, B, C or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

The new model costs twice more than last year‟s model

Mark the letter A, B, C or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

Although we are concerned about the problem of energy sources, we must not fail recognizing the need for environmental protection

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions from 33 to 51.

The company has to ___________ ways of reducing costs.

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions from 33 to 51.

It was such a shock to receive a letter like that ___________.