Talking about a hat that was bought yesterday.
Example: 晩ごはんの準備をします（今）。 → Answer: 晩ごはんの準備をしておきます。 Explanation: Prepare dinner now for later.
Focuses on using the past tense (た-form) of verbs or the noun + の construction. 終わった あとで
Situation: You see a clean car. Answer: 車が洗ってあります。 Explanation: The car has been washed.
Channels like "Yuuka's Channel" or "Arjun Tamang" offer step-by-step explanations of Renshuu B for Lesson 34.