阅读下面的文字，分别回答问题。

微藻——可循环的“绿色油田”

    ①由于石油资源的逐渐减少乃至最终枯竭，全世界将面临严重的能源危机，因此，世界各国都在积极寻找能够替代石油产品的可再生能源，其中，生物柴油就是一种重要的生物能源。提起生物柴油的原料，我们可能会想到油菜和大豆，用它们“体内”的油脂加工而成的生物柴油，能有效降低碳排放。然而，这两种作物的培育周期较长，占用农田较多，会产生“与人争粮，与粮争地”问题，从而导致“解决了能源危机，却出现粮食危机”的尴尬结果。此时，微藻进入了科学家们的视线。

    ②微藻是一种古老的低等植物，广泛地分布在海洋、淡水湖泊等水域，种类繁多。微藻可直接利用阳光、二氧化碳和含氮、磷等元素的简单营养物质快速生长，并在细胞内合成大量油脂。因此，微藻为生物柴油生产提供了新的油脂资源。

    ③与大豆、油菜和麻风树等油料植物相比，微藻的生长周期短，从初生到可以制油仅需一个星期左右，而大豆等油料植物一般需要几个月。此外，微藻的含油量高，油脂产率高，单位面积产油量是大豆的数百倍，每公顷可年产几万升生物柴油。微藻还不会占用耕地，利用滩涂、盐碱地、荒漠等，以及海水、荒漠地区的地下水等，就可以大规模地开发“微藻油田”，不会与农作物争地、争水。

    ④微藻在培养过程中还可固定大量二氧化碳，因此，利用微藻制造生物柴油能大量减少二氧化碳排放。据计算，每培养1吨微藻，需要消耗约2吨二氧化碳。此外，微藻在光自养培养过程中可利用废水中的氮、磷等营养成分，从而降低水体的富营养化，因此，微藻还能用于净化工厂排放的废水和城市生活污水。

    ⑤现在，我国已启动了微藻能源方面的首个973项目“微藻能源规模化制备的科学基础”。该项目有望在5年时间内开发出一个“微藻资源库”，提供适合在我国不同地方、不同气候条件下生长的藻株。今后，各地在建设“微藻油田”时，就可在资源库中挑选合适的微藻品种。该项目还将深入研究微藻产品的机理，力争提高微藻产油的效率，降低它的成本。此外，该项目还将通过对光生物反应器、培养工艺、采收、油脂加工及藻细胞综合利用的研究，建立一套中试系统，全面评估微藻产油的技术指标、经济指标和环境指标，大力推动我国微藻能源的产业化进程。

今年两会期间，***反复强调，要实现到2020年让7000多万农村贫困人口摆脱贫困的既定目标，时间十分紧迫、任务相当锗重。要采取产业精准扶贫一批、移民搬迁安置一批、低保兜底脱贫一批、医疗救助扶持一批的“四个一批”措施，坚决打赢这场攻坚战。根据材料下列推断正确的是（     ）

①致贫的原因多样，印证了矛盾具有特殊性的道理

②脱贫的手段各异，说明了同一事物在不同阶段的矛盾不同

③脱贫的时间紧迫，要集中力量解决矛盾的主要方面

④脱贫的任务艰巨，要求重视局部的发展打好扶贫攻坚战

    The holiday season isn't about shopping and gifts.____ However, holiday travel can be more expensive than gifts. Fortunately, the following tips will help keep your travel spending under control.

    Plan ahead. The earlier you book your travel, from airfare to hotels, the easier it is to find good deals.____ Your best prices on airfare come when you book three weeks before the plane leaves for domestic(国内的) flights. For international flights, consider booking 30 days in advance. Many experts point out that you should book travel between one month and three months out for high-traffic holidays.

    Book your air travel on cheaper days. Traveling by air on Tuesdays and Wednesdays often costs less than on Fridays and Sundays. During the holidays, it's not just about a specific day of the week. You also need to consider the days surrounding the holiday but days immediately before and after a holiday can be expensive. One of the best ways to save is to plan your air travel on the day of the holiday.____

    Consider traveling overnight. Red-eye flights and overnight flights often cost less than those at more convenient times.____  Traveling overnight can help you avoid a night in the hotel, as well as save your money on travel to your destination.

    ____ You can't bring liquids with you on the airline, but you can bring sandwiches and other snacks. When you're on the road, you can buy food at local groceries to make your own meals, especially if you have access to（可使用） a microwave.

A. Bring your own food.

B. Consider affordable accommodations.

C. Traveling by plane is not the best choice.

D. Plus, booking earlier can save your money.

E. For instance, traveling on Christmas Day might be a great deal.

F. A great deal of travel also takes place during this time of year.

G. Other choices include sleeper trains as well as overnight ferries.