Chinese has been added to the graduation exam list by Sophie School, an Italian high school and 29 students will take the test this year. This high school is mainly about language in northeastern Italy. It has become the first school in the country to list Chinese as a graduation exam subject. The Chinese course has been taught at this Italian school for 5 years, and 145 of its 910 students have chosen to study Chinese. Maria, director of the school, said Chinese will become a global (全球的) language in the future and they set up the course because many students had asked for it. "There were only a few schools in Italy which provided Chinese courses then, but now, Chinese courses have become an important part of our teaching plan," she said.

    Robert is a student in this school. He is going to take the Chinese test this year. He said that Speaking Chinese is not so difficult, it was difficult for them to understand the same word in different sentences and read Chinese poets, but writing Chinese characters (汉字) is the most difficult part of learning the language. "Although learning Chinese is difficult for Italian students, when considering looking for better jobs abroad, China must be my top choice," he said.

设第一象限内的点$\left(x,y\right)$满足$\left\{\begin{array}{c}2x-y-4\le 0\\ x-y\ge 0\end{array}\right.$若目标函数$z=ax+by\left(a>0,b>0\right)$的最大值是4，则$\frac{1}{a}+\frac{1}{b}$的最小值为(      )

希望小学三年级共有880人，平均分成8组，每组____人。

在南方有一种昆虫，与____一样，能引起人的兴趣。但不怎么出名，因为它不能____,它是____。