ACT English Adjectives vs. Adverbs: Know When to Use Each Form

Adjectives describe nouns. Adverbs describe verbs, adjectives, or other adverbs. Test: What word does it modify? If noun, use adjective. If verb/adjective/adverb, use adverb. Example: "She ran fast." Fast modifies ran (verb), so use the adverb form: "She ran fast." (or "quickly"). Example: "The fast runner won." Fast modifies runner (noun), so use adjective: "The fast runner won." The key is identifying what word you're modifying. Once you know, the correct form follows logically.

Another example: "She is happy." Happy modifies she (noun used as subject), so adjective is correct: "She is happy." (describes the person). But "She spoke happily." Happily modifies spoke (verb), so adverb: "She spoke happily." (describes how she spoke).

Mistake 1: Using an adjective to modify a verb. "She speaks clear" is wrong. Clear modifies speaks (verb), so use adverb: "She speaks clearly." Mistake 2: Using an adverb to modify a noun. "The quickly train arrived" is wrong. Quickly can't modify train (noun). Fix: "The quick train arrived." Mistake 3: Confusing feel/look/sound/taste (linking verbs) with action verbs. These linking verbs take adjectives: "She feels happy" (not happily). She is happy. But action verbs take adverbs: "She ran quickly" (not quick). Remember: -ly words are usually adverbs; forms without -ly are usually adjectives.

During practice, mark every adjective and adverb. Verify it modifies the correct word type (noun=adjective, verb/adjective/adverb=adverb).

Sentence 1: "She speaks clear about her ideas." Error: Clear modifies speaks (verb). Fix: "She speaks clearly about her ideas." Sentence 2: "The quick rain stopped." Correct (quick modifies rain, a noun). Sentence 3: "He drove slow through the intersection." Error: Slow modifies drove (verb). Fix: "He drove slowly through the intersection." Sentence 4: "The food tastes good." Correct (good is an adjective describing the food after the linking verb tastes). Sentence 5: "She performed the song beautiful." Error: Beautiful modifies performed (verb). Fix: "She performed the song beautifully." Identify the error and apply the fix to each sentence.

Find 10 adjective-adverb questions from a practice test. For each, identify what word is being modified and verify the correct form is used. By the tenth question, adjective-adverb distinctions will be automatic.

Adjective-adverb questions appear regularly on ACT English. Because the rule is simple (what word is being modified?), this is a high-return, learnable skill. Mastering this distinction picks up 1 point on the English section because the rule is consistent and errors are predictable.

Drill the modification test (what word is being modified?) daily this week. On every practice test, mark every adjective and adverb and verify it modifies the correct word type. By test day, you'll spot these errors automatically.