When you type in the if statement and the terminating colon, then press Return (or enter) on your keyboard, the Python interpreter realizes you have entered a compound statement.

当键入if语句和终止的冒号，并按键盘上的回车键时，Python解释器就知道您输入了一个复合语句。

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And "Discover Python, Part 5" introduces the concept of compound statements in Python, and the if statement and the while loop.

“探索python，第5部分”介绍了Python中复合语句的概念，并介绍了if语句和while循环。

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If it finds a match, the corresponding statement (simple or compound) executes.

若发现相符的，就执行对应的语句(简单或复合语句)。

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