Exercise 2. Read and fill in the missing words. Protects, straight, efficient, remembers, fall ill, defense, prevent, organisms, immune, divided
.
Our body has a powerful army that 1.

it from various types of threats. This personal
army is called the 2. ...
system. Every day we encounter a huge number of
bacteria, viruses and other disease-causing 3.
However, we do not 4.
every other day. Which is due to our immune system. The immune system can be
broadly 5.

into two parts - innate and adaptive immunity. Innate immunity is
the body's first natural 6.
..to any intruder. Its main goal is to 7.
...any intruder from entering the body.
There is also the adaptive immunity. This system is more 8.
as it can
differentiate between different types of pathogens.
The job of the immune system is to fight these pathogens and get them out of the body. What's so
incredible about the immune system is that it 9
how to fight the infection, so if
the pathogen comes back for round two, the body can beat it off 10.
away!​

nvironmental problems have become one of the most urgent problems of modern society. More and more people suffer from air and water pollution. Nature also suffers from land and nuclear pollution. The reasons for such environmental problems are numerous. Among them increasing number of cars in the streets, factory waste, millions of cut down trees, destroyed habitats of animals, contaminated rivers and seas. All these problems mainly arise due to human careless activities and gradually destroy our planet. If we look closely, we’ll notice that not only one city is under danger, but the majority of world population. Fortunately, there are many ways to suspend these problems. If everybody starts caring about the planet we live on, many environmental problems can be solved. For example, if we start recycling paper and cardboard, we can save lots of trees. If we start using public transport more than private cars, we can have less air pollution. Local governments can also help to prevent some problems, if they forbid logging companies to destroy the forests, or stop factories from polluting water. The most important thing is, of course, to start acting immediately, otherwise we might have to face many global disasters.

А - активный залог, П - пассивный.
1) А: The secretary is still typing the letter. (Секретарь все еще печатает письмо).
П: The letter is still being typed by the secretary. (Письмо все еще печатается секретарем.)
2) А: Mary made the fish (Мэри приготовила рыбу.) 
П: The fish was made by Mary (Рыба была приготовлена Мэри)
3) П: My  sweater was made in Italy (Мой свитер сделан в Италии)
А: They made my sweater in Italy (Мой свитер сделали в Италии)
4) Не знаю, почему в этом предложении используется Present Perfect. Правильнее использовать Past Simple:
П: Radium was discovered by Curie (Радий был открыт Кюри).
А: Curie discovered radium (Кюри открыли радий).
5) А: Snow covered everything (Снег покрыл всё).
П: Everything was covered by snow (Всё было покрыто снегом).
6) А: He pointed out the mistake to me (Он указал мне на ошибку)
П: I was pointed out the mistake by him (Мне было указано им на ошибку). Или The mistake was pointed out to me by him (Моя ошибка была указаны им)
7) А: The police is looking for the thief (Полиция ищет вора)
П: The thief is being looked for by the police  (Вор разыскивается полицией)
8) А: The boss offered a good job to me (Босс предложил мне хорошую работу)
П: I was offered a good job by the boss
Или A good job was offered to me by the boss (Оба варианта можно перевести "Мне была предложена хорошая работа")
9) А: They will discover a new branch of science (Откроют новое направление в науке)
П: A new branch of science will be discovered (Новое направление в науке будет открыто)
10) А: Tom made a hard work (Том проделал тяжелую работу)
П: A hard work was made by Tom (Томом была проделана тяжелая работа)
11) А: Beginners use that computer (Новички используют этот компьютер)
П: That computer is used by beginners (Этот компьютер используется новичками)
12) А: We sold the last French book (Мы продали последнюю книгу на французском)
П: The last French book was sold by us (Нами была продана последняя книга на французском)
13) А: We will settle your problems (Мы решим ваши проблемы)
П: Your problems will be settled by us (Ваши проблемы будут решены нами)
14) А: They have done this project (Они сделали этот проект)
П: This project has been done by them (Этот проект сделан ими)
15) А: We are making a tasty tea (Мы готовим вкусный чай)
П: A tasty tea is making by us (Нами готовится вкусный чай)