Which word in the sentence is adverb students apologized to teacher when they arrived late for their English class?

Here's why:

* Adverbs modify verbs, adjectives, or other adverbs. They tell us how, when, where, or to what extent something happens.

* In this sentence, "late" modifies the verb "arrived". It tells us *how* they arrived (they arrived at a time that was not on time).