下列各句中加线的成语，使用最恰当的一项是（    ）                    

计算，能简算的要简算．

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。

             Long ago, there lived in Greece a ____(learn) man. He was ____well-known for his knowledge of almosteverything that lots of people from all over the country came to learn fromhim. The great man taught his students whole-heartedly and answered theirquestions with great ____(patient).

           One day, a student asked him, “My dearteacher, didn't you say you yourself have many more questions about things thanwe do?____ I think we students have far more than you.”

           With a smile on his face, the teacher ____(draw) two circles, one as large as abig cake, the other smaller. Then he said, “Of course, I have learned muchmore. But ____is wrong to think ateacher has fewer questions than his students. Now, look at these two circles.The inside of the bigger one is my knowledge of things, and the inside of thesmaller one is____(you). Out ofthe circles is what is still unknown to us. Since mine is larger, I have ____(use) the longer line to draw thebigger circle. That ____(mean) Ihave more opportunities to face what is still unknown. And that's why I myselfhave more questions than you do. The ____(much) you learn, the more questionsyou have. You will never learn enough, you know.”