Unit 6 Nurturing Nature Using language 课件-2021-2022学年高中英语外研版（2019）选择性必修第一册

Present perfect continuous a. Wild animals such as these Tibetan antelopes have now been using these passages for years . 1. Which of these statements is true about sentence (a)? (1) Wild animals started using these passages in the past. (2) Wild animals used these passages only once. (3) Wild animals still use these passages now. a. Wild animals such as these Tibetan antelopes have now been using these passages for years . b. …before I know it, we have reached Tanggula Station. What is the difference between the expressions in bold in sentences (a) and (b)? have/has been doing have/has done 现在完成进行时 现在完成时 动作从过去开始正在进行 动作发生在过去 Now look for more sentences with the present perfect continuous tense in the reading passage, and summarise its use in your own words. 1. The train has been racing along steadily since it left Xining. 2. All this time, the song “Sky Railway” has been playing inside my head. 3. The journey has been flying by, ... 4. The Qinghai-Tibet Plateau has been attracting