What is the incorrect phrase in the following sentence? He will go to home when his math class finishes.

In the sentence "He will go to home when his math class finishes," the phrase "to home" is incorrect due to the preposition "to" being unnecessary. In English, the word "home" often functions as an adverb of place rather than a noun when indicating direction towards one's residence. Thus, the correct expression should simply be "He will go home."

The other components of the sentence, like "his" and "math class," are perfectly acceptable and serve to indicate possession and identify the specific class. The verb "finishes" is conjugated correctly for the subject, completing the sentence appropriately. Recognizing how "home" is used is crucial in ensuring grammatical correctness, as it affects clarity and fluency in writing and speaking.