1. The boy ran around the house.

2. He broke the plants.
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Q1: In #1, did he run around the house outside? Did he run outside, running around the house? Or did he run inside the house, making the living room or the kitchen messy?
Q2: Is #2 grammatical?

Sentence 1 could mean either inside or outside the house. At first reading, I took it to mean inside, and if that's true, then sentence 2 is correct.

Q1: Based on the information provided, the sentence "The boy ran around the house" does not specify whether he ran around the house outside or inside. It only states that the boy ran around the house without providing further details about the specific location.

To determine whether he ran around the house outside or inside, you would need to provide more context or additional information. Without more information, it is impossible to determine if he ran outside, making the house messy, or ran inside, making specific rooms messy.

Q2: Yes, sentence #2 "He broke the plants" is grammatically correct. It is a simple sentence that is ordered subject-verb-object. The subject is "he", the verb is "broke", and the object is "the plants."