题目

Modern life is impossible without travelling. There are four main 【1】 for most people to travel. The fastest way of travelling is by air. With a modern airline, you can travel in one day or less to your places. But it 【2】 people a month or more to get to these places several hundred years ago 【3】 they had to walk or ride horses to the place where they wanted to go.Traveling by train is 【4】 than by air, but it has its advantages (优势). 【5】, you can spend much less money 【6】 train tickets. Second, you can enjoy the beautiful scenery out of the window during your journe在人体内，下列各种现象中不能促进肾小管重吸收水分的是A.组织液渗透压升高B.血液中抗利尿激素的含量升高C.血浆渗透压升高D.肾小管内的原尿浓度升高