题目

阅读下面短文，在空白处填入 1 个适当的单词或括号内单词的正确形式。 By far, the most (technology) challenging railway ever built was probably the Qinghai-Tibet Railway, completed in 2006, which connects Xining to Lhasa. The railway was first planned in the 1950s, but the technical difficulties were too much (overcome). It was not until 1984the first 814-kilometer section of the railway, from Xining to Golmud, was completed. The biggest issue was the permafrost(冻结带)-frozen earth. In the summer, usually melting at a fast speed, the top layer of the permafrost turns to mud,(make) the ground unstable. A(various) of solutions were used to get around this. In some cases, railway bridges (build). In other cases, engineers installed pipes under the ground to keep it frozen during the summer. Finally, in some areas, it was impossible to build the railway over the permafrost, engineers tunneled(开凿隧道) through it. It is hoped that the experience of building the Qinghai-Tibet Railway can be used in new project, linking China with Pakistan. This railway(travel) 1,000 kilometers through the Pamir Mountains, which are nicknamed the Roof of the World. Building such a railway will be(doubt) a technical challenge. It has not yet been announced when construction on this project will start. 答案：【1】technologically【2】to overcome【3】that【4】making【5】variety【6】were built【7】so【8】a【9】will travel【10】undoubtedly

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