Spending too much time on the Internet leads to an internet_______, which can destroy a healthy balance of interests and activities in your teen's life.

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.

He _______ three books and he is working on another one.

What is the main idea of the passage?

 In this way (46)_______ very hard rocks are worn away by the wind.  

Retailers have taken to the ecommerce world because________.

Not until all their demands had been turned down did the workers decide to go on strike for more welfare.

Mark the letter A, B, C or D on the answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following sentences.