Exercise 1. Put the verbs in brackets into the correct form (the to infinitive or V + ing) 1. Don't expect him … you any money. (lend)
2. She is too old … climbing like she used to. (go)
3. She gave up … because she had a very poor voice. (sing)
4. During your trip you can even spend some time … a few Chinese phrases. (learn)
5. I hope … you soon. (see)
6. I can't help … at him. (laugh)
7. Please, stop … it. (do)
8. He finished … the newspaper. (read)
9. He suggested … into town. (drive)
10. She seems … difficulty coping with her studies. (have)
11. I'm very glad … you here. (see)
12. They discussed … the company. (sell)
13. I'm looking forward to … from you soon. (hear)
14. He left the shop without … (pay)
15. Don't forget … your camera. (take)
2. Infection can enter the body through various ways. The text mentions that infection may enter through skin cuts or abrasions, the eyes, or it may also be swallowed. This means that any open wounds, cuts, or even the mucous membranes in the eyes and mouth can serve as entry points for microorganisms to invade the body.
3. Ancient people believed that the body's first line of defense against infection was an intact surface, such as the outer layer of skin and the protective outer layer of mucous membrane. They recognized that a barrier in the form of healthy skin and mucous membranes can prevent microorganisms from entering the body and causing infection.
4. The second line of defense starts its action if the infection manages to bypass the body's first line of defense. In the text, it is mentioned that if infection had passed the intact surface, the liquid secretion produced by the protective surfaces would start its action. This means that the body's second line of defense is the production of substances like saliva, tears, sweat, and gastric juice that have antimicrobial properties and can help neutralize bacterial poisons and kill some microorganisms.
5. The liquid secretion, such as saliva, tears, sweat, and gastric juice, is produced by the protective surfaces, like the salivary glands, mucous membranes, and sweat glands. These secretions contain substances that can help fight against microorganisms and protect the body from infection.
6. Saliva can play a protective role against infection. It neutralizes some bacterial poisons and can kill certain microorganisms. This means that saliva contains substances that can help eliminate harmful bacteria and prevent them from causing infection.
7. Tears and sweat also have a similar effect to saliva. They contain substances that can help fight against microorganisms. The acidity of sweat and the antiseptic properties of tears can help kill many bacteria present on the skin and prevent the spread of infection.
8. The third line of defense called immunity has been discovered now. This means that the understanding and development of the body's immune response to infections have been studied and researched in more recent times. The immune system plays a crucial role in recognizing and destroying harmful microorganisms, as well as providing long-term protection against future infections.
9. The last line of defense, if the body's defense mechanisms fail to prevent infection, is a response called inflammation. Inflammation is a natural response of the body to infection, injury, or foreign substances. It is characterized by redness, swelling, heat, and pain in the affected area. Inflammation helps to isolate and eliminate the source of infection and initiate the healing process.
Overall, it is important to understand the sources of infection, how it can enter the body, the body's defense mechanisms, and the steps taken by the body to fight against infection. This knowledge is crucial in preventing the spread of infection and maintaining good health.