一个平面截圆柱，则截面形状不可能是（　　）

材料：一般地，n个相同的因数a相乘： 记为aⁿ．

如2³=8，此时，3叫做以2为底8的对数，记为log₂8（即log₂8=3）．

一般地，若aⁿ=b（a＞0且a≠1，b＞0），则n叫做以a为底b的对数，记为log_ab（即log_ab=n）．如3⁴=81，则4叫做以3为底81的对数，记为log₃81（即log₃81=4）．

问题：

阅读下面材料，在空白处填入适当的内容(1个单词)或括号内单词的正确形式。

    We  are what we eat because what we eat every day has ____ great impact on our health.Therefore，we should make everyeffort to change our bad eating habits. ____ we all know，baked or fried foods may be ____(taste) , but eating toomuch of them will ____(probable) result in some illnesses. Moreover, some foodthat costs us a great deal of money and is not healthy is junk food.

____(compare)withpeople in the West, Chinese people used to eat more grain and vegetables, but____(little)meat, which is a good eating habit. However, things are quitedifferent now. With the rapid economic ____(grow)of our country, we now areeating a lot of food that is high in sugar and fat. We ____(run) the risk ofeating out without considering the balance of our diet.

      The food we choose affects our health, so wemust keep ____mind that the food we choose should give ____(we) the nutrientswe need.