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Renewable energy is becoming _______, so lots of people can afford it.

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Many endangered species will keep losing their _______ unless we reduce deforestation.

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Nuclear, wind, and solar power are _______ energy sources.

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The huge crowd is _______ about the local water pollution, showing lots of signs and banners on the streets.

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In this zoo, some scientists are trying to _______ some species that are seriously endangered.

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If factories _______ proper filters, they wouldn’t have released so many harmful gases into the air.

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The more we ignore climate change, _______ serious its impacts on the environment will be.

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The less smoke is released into the air, the _______ the atmosphere becomes.