Climate change has caused a rise in sea levels. This has increased the amount of salt in fresh water____(use) on coastal farms. As____ result, farmers are ____(gradual) unable to use fields close to the sea.

    However, Marc Van Rijsselberg, a farmer in the Netherlands is now using a____(mix) of sea and fresh water ____(grow) healthy and tasty vegetables.

    He teamed up with scientists from the Free University and divided a farm ____eight negated areas. Separate pipes pumped fresh and sea water, and a computer program created water with eight levels of salinity（含盐度）．

    The water levels and the levels of salinity were controlled by computerized measuring devices called "sensors". Mr. Van Rijsselberg said he was able to harvest vegetables from most of the eight testing areas. He said the vegetables were smaller than ____grown in fresh water. But he said they also had more sugar and salt, so they tasted much____(good).

    He found that potatoes grew better than the other vegetables in the combination of sea and fresh water. Mr. Van Rijsselberg said four kinds of these potatoes would be sent to Pakistan____thousands of hectares of land ____(damage) by salinization (盐化作用) last year.

下列各句中，没有语病的一项是（      ）

若α为锐角，已知cosα=$\frac{1}{2}$，那么tanα=____ 

补写出下列名句名篇中的空缺部分。

①大江东去，____。故垒西边，人道是，____。 

(苏轼《念奴娇·赤壁怀古》)

②五步一楼，十步一阁。____，____。 

(杜牧《阿房宫赋》)

③句读之不知，惑之不解，或师焉，或不焉，____，____。 

(韩愈《师说》)

④时维九月，序属三秋;____，____。 

(王勃《秋日登洪府滕王阁饯别序》)

“山上多植树，胜似修水库，有雨它能吞，无雨它能吐”，这条谚语形象地说明森林对环境的作用是（  ）