Populations of living beings are constantly changing. The number of humans, animals, insects, or plants living in a given area can vary because of two kinds of factors: biotic and abiotic Biotic factors are living factors that can influence the size of populations, such as predators or other species competing for food. Abiotic factors are nonliving things in the surrounding environment that can cause population changes, such as weather or sunlight. Biotic and abiotic factors cause continual changes in the number of individuals that make up a population of organisms.
Population Changes 這個(gè)標(biāo)題無疑是重要的關(guān)鍵詞,隨著閱讀部分掃描的進(jìn)行,可以補(bǔ)助到two factors這兩個(gè)詞匯,已經(jīng)對(duì)應(yīng)兩個(gè)因素biotic以及abiotic兩個(gè)分類。那么結(jié)合T4的出題規(guī)律,這就是一句帶著關(guān)鍵信息的總起句,重組一下就是對(duì)于整篇文章(包括閱讀和聽力)的Introductory Sentence.即是 The lecture is mainly about two factors that can influence the population changes of species.