四、同时，我们也可以使用sin、cos以及一些其他的在MATLAB内部设定好的函数进行计算；（在调用诸如sin、cos等函数时要使用括号）
4. At the same time, we can also use sin, cos and some other functions set in MATLAB to perform calculations; (brackets should be used when calling functions such as sin, cos, etc.)
五、右边的“工作区”里储存着我们定义过的变量，有一个变量是“ans”,代表结果，每次计算，ans的值都会被重新赋予；想要清除某一变量，输入“clear”和想清除的变量，如果在clear后面不加变量，则会清除所有变量；“clc”清除命令行窗口里的命令；
5. The variables we have defined are stored in the "work area" on the right. One variable is "ans", which represents the result. Each time the calculation is performed, the value of ans will be re-assigned; if you want to clear a variable, enter "clear" "And the variable you want to clear. If you do not add a variable after clear, all variables will be cleared; "clc" clears the command in the command line window;
