Ozone is an unstable faintly blui gas that is the most chemical active form of Oxygen.

Choose the underlined word or phrase that needs correcting: 

Vietnam has established many national parks to protect wildlife.

Choose the correct answer to each of the following questions. "My Son Sanctuary is a large complex of ______ relics comprising more than 70 architectural works such as towers, temples, and tombs."

Jessamyn West’s first and most famous novel, the friendly persuasion, describes the life of Quaker farmed family in the mid-1800’s.

Choose the correct answer to complete the sentence. "The Braille alphabet has been one of the _______ inventions in human history"

There are none young single people living n this town – old people and young families.

I did not realize that I had left my umbrel on the bus when it started to rain

A City Professor reported that he discovers vaccine which has been 80 % effective in reducing the instances of tooth decay among mall childre

Choose the word(s) OPPOSITE in meaning to the following word(s). "Abundant"

Among world’s 44 richest countries, there has been not war since 1945

Choose the correct answer to each of the following questions. "The Imperial Citadel of Thang Long was first built during the Ly Dynasty and then expanded by ______ dynasties"

Since infection can cause fever as well as pain, it is a good idea to check a patient’s temperature.

This new nice flat looks perfect for  young couple.

Choose the correct answer. "_________ my granfather is old, he still goes jogging."

There is  evidence that the caribou originated into North America and crossed over all land bridge into Asia and evolved into th World’s reindeer.

Choose the correct answer to complete the sentence. "He traveled extensively and used the knowledge gained _____ his travels as the basis for his early novels"

The development of professi sports in the United Stated dates back to nineteenth century.

Tuan writes more  .......   with fewer mistakes than the previous term.

Kiwi birds search ground with the bills for insects, worms, and snails to eat

The student realized with appointment that he had learned new nothing in the lecture

Although the Red Cross accepts blood from most donors, the nurse will not let yougive blood if you have just had a cold.