My observation tells me that in most supermarkets plastic bags are offered by salespeople according to customers' actual needs.

通过亲自观察我发现，在大多数超市里收银员都是根据客户的实际需要来提供塑料袋的。

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He set up a corn popper in front of his store and offered free bags of fresh, hot popcorn to his customers, who were drawn by the aroma.

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