nobody likes insects. they are annoying and sometimes dangerous. some of them bite us and give us 51 ; others bite us and give us big red 52 . some do not bite, 53 they just fly round our heads or crawl round our houses and gardens. and we do not like any of them 54 those lovely butterflies.
but insects are interesting. first, they are very 55 animals. three hundred and twenty million years ago there were no men or other mammals in the world but there were insects. today, 56 every square mile of land there are millions of them flying and crawling 57 . second, insects are very 