tailieunhanh - Barron's writing for the toefl ibt part 9

Is there a spell checker or grammar checker on the computer? No, You will have to do your own proofreading* Don't worry about a few spelling errors or a few mistakes with punctuation or grammar. A few small errors will not count against your score. Hint: If you are unsure how to spell a word, use a word you do know how to spelL | 56 Writing for the TOEFL iBT READING IDEA MAP Writing Skills Integrated Task 57 Lecture 6 Track Listen to the lecture. Write your notes on the Lecture Idea Map. LECTURE IDEA MAP 58 Writing for the TOEFL iBT Reading 7 Read the passage. Write your notes on the Reading Idea Map. Pollution of our oceans is a serious problem. There are different sources of ocean pollution and much of it results from activities that take place on land. In fact 80 of ocean pollution originates on land. For example oil is one of the major sources of ocean pollution but only about 12 of this type of pollution results from oil spills at sea. Another 36 of it comes from waste from cities and factories which travels to the ocean through rivers and drains. Fertilizers are another serious source of ocean pollution. Fertilizers wash off farms and lawns and eventually end up in the ocean. Once in the ocean they allow algae to grow. The overgrowth of algae depletes the ocean of oxygen and suffocates other marine plants resulting in dead areas. There are several large dead areas in the worlds oceans including the Gulf of Mexico and the Baltic Sea. Garbage is another type of pollution in our oceans and it can seriously harm marine animals. One of the worst culprits is plastic. This material does not break down easily. Animals often mistake it for food and eat it. Plastic bags can block an animals breathing passage. The plastic rings that hold packs of cans together can choke birds and other small animals. Toxic chemicals also cause serious pollution problems. Until the 1970s toxic waste chemicals were freely dumped into the oceans. In the 1970s laws were passed banning such activity. However run-off from manufacturing and disposal sites as well as accidental leaks continue to pollute our oceans with toxic chemicals. These chemicals accumulate in the animals that ingest them and move up the food chain. They eventually end up in the seafood that we .