Linguistics is the scientific study of language, and involves an analysis of language form, language meaning, and language in context. The earliest activities in the documentation and description of language have been attributed to the 6th century BC Indian grammarian Pāṇini, who wrote a formal description of the Sanskrit language in his Aṣṭādhyāyī.
Protection and sustainable use of water supply is one of the most important environmental issues facing humanity. Groundwater is the primary source of drinking water for much of the world, as well as being vital for agriculture and industry, but it is under threat from pollution.
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