The sentence "A scared blowfish puffs up into a spiny ball." is grammatically correct. Let's break it down:
- "A scared blowfish" is the subject. "A" is an article, "scared" is an adjective describing the blowfish, and "blowfish" is the noun.
- "puffs up" is the verb phrase showing the action the blowfish does.
- "into a spiny ball" is a prepositional phrase that explains what the blowfish becomes when it puffs up.
Everything fits together nicely, and the sentence is clear and easy to understand for a young learner.