国家规定每年的12月4日，4周岁以下的儿童必须服用脊髓灰质炎糖丸，以预防小儿麻痹症．这是因为儿童服用糖丸后，能在体内产生（  ）

    Natural resources are things that we use that come from the earth. Our natural resources are limited(有限的). This means that they will not1forever. Some are renewable, like when you plant a new tree when you cut one down. Others are not renewable, like when you dig coal(煤) out of the 2Once it is used, it is gone.

    People realize the 3 that the earth's natural resources are limited, and can do things to help conserve(节约) those resources.4you try to conserve a natural resource, you try to use less of it, so it does not get used up so5One way that people conserve fuel, like gasoline, is by riding a bicycle or walking when the6is short instead of driving everywhere.

    Water is a very important natural resource because we all need it to stay 7We can conserve water8making sure that our pipes and taps do not leak(泄露). We can also make wise choices to conserve water, like only using the dishwasher or washing machine when they are full. Everyone can make contributions to protecting natural resources.

阅读下面一首词，回答相关问题
                                                                                             宴  词

                                                                                         （王之涣）
                                                                     长堤春水绿悠悠，畎入漳河一道流。

                                                                     莫听声声催去棹，桃溪浅处不胜舟。
注：宴词：写于送别宴席上的诗。畎：田间小沟