1. Ask the Key Question:
Direct Object (DO):
“Subject + Verb + What/Whom?”
If the infinitive answers this, it’s a direct object.
Example: “She loves to sing.”
“Loves what?” → “to sing” (Direct Object).
Adverbial Infinitive:
“Subject + Verb + Why/How/When/Where?”
If the infinitive answers this, it’s adverbial.
Example:
“She exercises to relax.”
“Exercises why?” → “to relax” (adverbial).
2. Try the “In Order To” Test:
If you can replace the infinitive with “in order to”, it’s adverbial:
“He studies to pass.” → “He studies “in order” to pass.” (Adverbial).
If not, it’s likely a direct object:
“She wants to sleep.” → ❌ “She wants “in order” to sleep.” (Makes no sense → Direct Object).
3. Examples to Compare:
She is learning to swim.
Learning what? “to swim” → Direct Object
He is shouting to help.
Shouting why? “to help” → Adverbial
They hate to wait.
Hate what? “to wait” → Direct Object
“She naps to recover.”
Naps why? “to recover” → Adverbial
She wants [to travel the world].
Wants what? → “to travel the world” Direct Object.
They hate [to wake up early].
“Hate what?” → “to wake up early” Direct Object
He attempted [to climb the mountain].
“Attempted what?” → “to climb the mountain” Direct Object.
I wish to buy a car
“Wish what” → “to buy a car” Direct Object
She kills to feed her anger”?
why does she kill? to feed her anger. adverbial
She trains to become the best
Why does she train? to be the best. –> adverbial