Free samples are below-the-line advertising.

赠送样品属于线下广告。

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Below-the-line advertising has the advantages of being cheap and very easy to produce.

低层次广告宣传品有成本低廉，编写容易的优点。

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We need to take a firm line on tobacco advertising.

我们需要对烟草广告采取强硬的态度。

《牛津词典》

They want direct results which come from promotions or below-the-line advertising.

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The rewards for giving employees what they want in this regard are many, including the fact that your dedicated employees become your first line of advertising because they know personally what your company stands for and are proud to promote it.

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When it comes to online brand advertising, even that line is blurred with promotional advertising.

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