She gave him her word that she would return by noon.

gave 是动词 give 的过去式，意思是"给予"。 him 是人称代词 he 的宾格形式，意思是"他"。 her 是形容词性物主代词，意思是"她的"。 word 在这里指"承诺、保证"，而不是字面意义的"单词"。 gave him her word 是一个固定搭配，意思是"向他作出承诺/保证"。