Most of the students in this class __________ from South Africa 

Air pollution, together with littering, are causing many problems our large, industrial cities today.

Mutualism is a relationship between animal species which both benefit.

It should be assume that the lower the price, the happier the buyer

Either humans and animals learn by experience, and what is learned influences the planning and carrying out of simple action

The oxygen in the air we breathe has no tasted , smell, and color

British people living outside  UK have to become accustomed to the image of Britain that appears to exist all throughout round the world

He has less friends his class now than he had last year .

Commercial letters of credit are often used to financing export trade, but they can other uses.

Ozone is an stable faintly bluish gas that is the most chemical active form of Oxygen

Light rays what enter the eye must focused onto a point on the retina in order forclear visual image to form.

Each chemical (element is characterized to the number of protons that an atom of that element contains, called its atomic number.

Nobody bothered with telling me that the school had decided to have a pecial holiday on Friday.

The extraordinary beautiful of orchids makes them the basis  of a multimillion-dollar floral industri.

The diary it was kept secret until the end of the war in fear of reprisalsthe occupying army.

We chose (to take trip to the Far East because it was advertised adventurous and intrigued

In the early twentieth century, there was considerable interesting among sociologists in the fact that in the United States the family was losing traditional roles

Find mistakes and correct

Education is desperately needed in countries where a high percentage of the population are illiterate

He had so a difficult exercise that he couldn’t do it

Earwax lubricators and protects ear from foreign matter such water and insects

People who exercise regularly are less likely develop heart disease than is those who do not keep fit