1easy: this is an adjective and is often used as a predicative. Object, object complement. The verb behind this question is to modify the math problem. Describing this math problem is very simple. 2easily is an adverb, often used to modify verbs and adjectives (emphasis). This question modifies the verb do. You can also modify adjectives, such as truly (adverb) and honest (modesty) to emphasize how deep this modesty is, understand?