2014年4月雅思考试摸底题及答案(第三套)_第2页

　11. Wars often drive technological development and many exciting____________________-____________________, such as the development of Radar from the second world ar, often result.

　　12. A group of people who leave their own country to live together somewhere else, but remain citizens of their

　　homeland, usually establish a ____________________ in the new territory.

　　13. Micro-organisms that can cause serious infections and diseases are called ____________________.

　　14. The traveller found the country very unfriendly, unwelcoming and ____________________ because nobody

　　would offer him food or shelter when he was destitute.

　　15. The presidential ____________________ were invited to take part in a TV debate before their election took

　　place, but both refused the invitation.

　　16. If chefs do not wash their hands before preparing food, they could ____________________ it with bacteria or

　　viruses from their own skins which could poison a lot of their customers.

　　17. We usually become ____________________ to a disease after we have had it, or had a vaccination against it,

　　so that we avoid catching it in the future.

　　18. The food supply was ____________________ because it became contaminated when harmful bacteria was

　　spread around the kitchen by an electric fan.

　　19. Prolonged heating and disinfectant have a ____________________ effect because both will kill germs and

　　bugs when applied to decontaminate an object.

　　20. A ____________________ is a small part or example of something collected by a scientist for further study nder laboratory conditions.