All you had to know is the word "Dog" and the plural morpheme 's' and you could put them together to create a word.

你只需知道"狗"这个词以,及复数语素'们',你可以将它们组合在一起来创造出一个词

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So, "Dogs" and "Complained" are one word, but two morphemes and what this means is that you make the word by putting together two morphemes.

因此,"狗狗们"和"抱怨的",都是由两个语素组成的单一词,这也就意味着,你将两个语素组合在一起成为了一个词

耶鲁公开课 - 心理学导论课程节选