题目内容

【题目】在黄土高原上下列哪种活动是属于不合理的生产

A.植树种草B.建梯田、修挡土坝

C.退耕还林、还草D.陡坡种植粮食

【答案】D

【解析】

黄土高原是我国水土流失最严重的地区,主要原因是土地利用不当,坡面陡峻、土质疏松、地面植被不良、耕作不合理及滥伐森林等。水土流失会对流失区的农业生产及下游河道带来严重危害,必须采取水土保持措施进行防治。针对上述因素,如植被不良,应植树种草;坡面陡峻,可建梯田、修挡土坝,阻挡水土流失;退耕还林、还草是防止水土流失的一项可行办法,而陡坡种植粮食,属于耕作不合理,易造成水土流失。

黄土高原生态环境脆弱,在经受人类活动的破坏后,很难恢复。要实现黄土高原的社会、经济的可持续发展,关键是加强生态建设。陡坡种植粮食容易导致水土流失的加剧;故选:D

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【题目】 In our life, there are many messages that tell us to be healthy. We may make much effort to achieve this goal. But really, it doesn't have to be so hard. Simply going for a walk—especially if you do it regularly and outdoors—is a lowstress, lowimpact(低强度), and an easy way to get lots of health benefits. It can be a happy time—spend alone or together with friends, in sunshine and the fresh air. Let's see the benefits of going for a walk.

Firstly, it makes you have a good mood. Studies show that walking outdoors can help relieve(释放) stress. Those who take a 90minute walk outdoors have less negative thoughts about themselves.

Secondly, it improves your heart health. Just 30 minutes, walk a day has been proved to improve blood pressure and reduce your risk of coronary heart disease and stroke. This can be finished easily by simple actions like parking farther away from buildings, climbing stairs, and pacing while talking on the phone.

Thirdly, it can reduce the sugar intake(摄入量). When_you_want_to_eat_a_sweet_snack,_go_for_a_walk__ One study shows that taking a 15minute walk helps people cut their chocolate intake in half.

The last but not least, it improves your brain health. Going for a regular walk has been related to increasing brain plasticity(可塑性), and developing the ability of creativity.

Therefore, let's make going for a walk become a routine.

1完成句子We may ________________ to achieve the goal of keeping healthy.

2完成句子Going for a walk is a lowstress, lowimpact and an easy way to get lots of ________________

3简略回答问题How long should you walk to have less negative thoughts about yourself?

________________________________________________________________________

4找出并写下第三段的主题句。 ________________________________________________________________________

5将文中画线句子译成汉语。________________________________________________________________________

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