Adverb of purpose expresses the purpose of an action which the verb directs. Adverb of purpose is commonly in the form of a phrase or a clause, rather than a single-word adverb. But the most common form of adverb of purpose is a to-infinitive clause. And adverb of purpose is usually placed at the end position of a clause.

Examples:
1. I stay awake to finish my task.
2. She climbed the mountain to see a great view from the peak.
3. He went away to avoid her.
You can also use the conjunctions that, so, so that, in order that, in order to, and lest to introduce the adverb of purpose.
Examples:

• I take a bath that I feel fresh.
• She studies hard that she can pass the final test.
• I always pay attention to the teacher’s explanation so I can understand the subject well.
• He cleaned the room so that we could stay comfortably in it.
• We painted the wall white so that it looks larger.
• Regia always wakes up early in the morning in order that she can breathe the morning fresh air.
• We arranged the books alphabetically in order to make them easy to get when needed.
• We treat our guests very well lest they complain about our service.

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