阅读下面的短文，并根据短文后的要求答题。（请注意问题后的字数要求）
Chhinanews Lhasa ,Dec ,12-A science forum that focused on the environmental change and its impacts on the Qinghai –Tibet Plateau as well as the regional development strategies was recently held at the Fragrant Hill in Beijing ,Staring From Monday ,. Chinese meteorological departments kicked off an atmospheric scientific experiment on the Qinghai-Tibet Plateau, The experiment will last for a year .
Recently ,the atmospheric science data gathered on the Qinghai-Tibet ,Plateau has aroused great interest among international science circles and media around the world ,It is said that over the past two decades ,Chinese scientists had carried out two atmospheric experiments on Qinghai----Tibet Plateau and obtained high –resolution data through these experiments ,This time ,the experiment will be carried out in two monitoring stations set in the eastern part of the plateau ,in these stations ,scientists will make some intensive observations of the atmospheres in the east to the Qinghai-Tibet Plateau and the lower reaches of the Yangtze River ,With these ,scientists will try to upgrade their data forecasting mode and improve their forecasting capability .
Qinghai-Tibet Plateau covers a vast area of land and the geological feature there is rather complicated Since there are not many monitoring stations set up there , scientists; information about the plateau is rather limited ,___________ they cannot make accurate forecast about the precipitation on the plateau and on the lower reaches of the Yangtze River ,It is said that there are rich hydropower resources in the eastern part of the plateau ,China plans to establish some hydropower stations in the upper reaches of the Yangtze River ,When the construction is completed ,these hydropower plants are able to generate electricity twice that produced by the Three Gorges Dam .
1．What is the main idea of the passage? (Please answer within 10 words)
2．Which sentence in the passage can be replaced by the following one?
The sources obtained through experiments carried out on the plateau have appealed to the attention of the science field at home and abroad .
3．Please fill in the blank in the third paragraph with proper words or phrases to complete the sentence (Please answer within 5 words)
4．Why is it difficult to carry out the experiment on the plateau?(Please answer within 30 words )
5．Translate the underlined sentence in the second paragraph into Chinese