1. To be poor, he could not buy the sports car.

2. Being poor, he could not buy the sports car.
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Which one is correct? Is #1 correct grammatically?

Both sentence constructions are grammatically correct, but they have slightly different meanings and implications.

In sentence #1, "To be poor" is used as an infinitive phrase acting as an adverbial clause of purpose. It suggests that the reason or purpose for the person's inability to buy the sports car is their poverty. This construction emphasizes that poverty prevented him from purchasing the sports car.

In sentence #2, "Being poor" is a gerund phrase that functions as an adverbial clause of reason. It conveys that the person's poverty is the cause or reason behind their inability to buy the sports car. This construction highlights the cause-effect relationship between poverty and not being able to afford the car.

In terms of meaning, both sentences essentially convey the same idea, but the emphasis and perspective differ slightly. Sentence #1 specifically highlights poverty as the motivation or purpose for not buying the car, while sentence #2 focuses on poverty as the reason or cause for the person's inability to make the purchase.