Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

By trial and error, we finally got the machine to work.（）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

Occasional loss of livestock must be weighed against the good these animals do in maintaining the balance of nature.（）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase. 

What breathtaking impertinence to advertise on your soap or washing powder or dog food or whatever.（）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

The person thanked me and put me completely at ease.（）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase. 

The third meaning of the term “foreign exchange” is that it covers, in a general way, the rates at which foreign exchange is quoted.（ ）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

Regardless of their direction or form, computer developments and uses of the future will depend on the cleverness and skill of men.（）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

The British government has been urged to make an inquiry into a nuclear plant because there have been too many accidents there.（ ）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

Errors occur because men grow tired and can be distracted.（）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

Concentrated eye contact helps you listen more effectively, and customers intuitively respect people who look them in the eyes.（）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

“Why didn't President Clinton get credit for the good economy?”（）

natural 这个单词的意思是（ ）

Directions: Read each of the following sentences carefully, and choose A,B,C or D that has the closest meaning to the underlined word or phrase.

The boss dictated a letter to his secretary.（ ）