These words are related, but different. 这些词是相关的，但又是不同的。 Also, I have never needed to use the word "metrical" in my life. 此外，在我的生活中，我从来不需要使用“metrical”这个词。 But here is an explanation. 但这里有一个解释。 rhythmical = something with rhythm or recurring with a measured regularity. For example, most music could be considered rhythmical. 有节奏或有规律地反复出现的事物。 例如，大多数音乐可以被认为是有节奏的。 Also, a machine that makes a sound again and again, like a drum beat. A jackhammer or an engine for example. 此外，一台机器会一次又一次地发出声音，就像打鼓一样。 例如手提钻或发动机。 metrical = this is a word that is more about describing the way that poetry is arranged. Many poems have a mathematical arrangement that is like a type of rhythm but we sometimes call it a "meter." 这个词更多的是描述诗歌的排列方式。 许多诗歌都有一种数学排列，就像一种节奏，但我们有时称它为“meter”。 To clarify, normal people don't usually use these words. Good luck.