Why is most of the water now safe, but now it is backward?

Now is an adverb of time, which can modify nouns, verbs, adjectives and adverbs. Adverbs can be placed in different positions in sentences, and of course the modified words are different. At the back, it is emphasized that the water can be safely drunk now. If you put it behind the drink, it is emphasized that water is safe to drink now.

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