Far from constituting a market in itself, this activity is merely ancillary to the market in motor cars, the open and highly competitive nature of which is undesirable.

这样的行为，其本身远不能构成一个市场，而仅仅是附属于机动车市场的一个行为，并不需要公开和高度的竞争性。

youdao

The self-employment activity can be part time, and it can be ancillary to full time employment elsewhere.

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Indirect spending reflects increased business-to-business activity that stems from increased visitor activity (e.g. if local hotels outsource their laundering and catering services, then those ancillary businesses see money dollars when the hotels get busier).

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