题目

if 7 is less than 4,then 7 is not a prime number（素数）.
7 is not less than 4.
_____________________
7 is a prime number.
就是不知道横线里面填什么!求高人指教一二!

提问时间：2021-03-02

答案

这是归纳法三段论,横线上填的是归纳原理,即the number that is not less than 4 is not a prime number
结论应该是7 is (not) a prime number.多了一个not
更准确的讲,第一行应该是the number that is less than 4 is not a prime number
第二行7 is not less than 4.
第三行 7 is not a prime number.