A purpose or reason clause needs a main clause to make a complete sentence.

目的状语从句和原因状语从句与主句一起构成完整的句子。

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The purpose of the General Welfare clause is to provide a reason, motivation, and purpose to the proper exercise of the Powers the Constitution specifically grants to Congress.

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For this reason, the mandate also cannot be justified under the Necessary and Proper Clause, because that clause can effectuate only those powers that Congress actually possesses under the Commerce Clause, not create new ones.

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This clause provides these companies with the option to raise rates at any time, for any reason.

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