So in other words, if thankful is still false at this point, it means this condition did not work out very well, and so I'm going to do this block of code again.

换句话说，如果thankful在这时候还是false值，这表示这个条件没有实现地很好，所以我将再次去处理这段代码。

哈佛公开课 - 计算机科学课程节选

As an aside, if you ever just have one line of code that you want to execute, one puzzle piece in Scratch terminology, ; you actually don't need the curly braces; you only need the curly braces if you have two or more lines of code that you want to execute if that condition is true.

此外，如果你只有一行代码,需要执行，在Scratch，术语中叫做,一句代码，你就不需要使用花括号了;,如果那个条件成立，你有两行或更多行的代码时需要执行时,你就需要花括号。

哈佛公开课 - 计算机科学课程节选

So in other words, if you terminate these lines early, if you terminate the four loop early, if you terminate an if condition early with that semicolon, the code may very well work; and this is a common source -- of frustration and conundrum because you don't -- because your code looks right and yet it's misbehaving, but that semicolon means stop looking for subsequent lines of related code.

换句话说，如果你用分号过早的终止了这些代码行，如果你过早地终止了那个for循环，如果如此,一个if条件，代码可能可以运行，这就是,挫折和问题产生的源头，因为你没有-,因为你的代码看起来是正确的，但是运行是错误的，那个分号的意思是,停止寻找后面相关的代码。

哈佛公开课 - 计算机科学课程节选