I don't watch TV.

Zero

It depends on the ad. If it's actually a good ad, then it may take many viewings to tire of it. But bad ads are tiresome right from the get go

Once is enough in some cases.

Have you seen the trailer for Bridget Jones' Baby ?

Yuck.

Depends on the commercial/trailer. It could be one time, it could be never. So my answer is, it varies.

Uuuuuh... Thousand times...... I've watched the "Tell me.... Do you bleed? ....... You will." part of the BvS trailer more times than I can count. ᶘ ͡°ᴥ͡ °ᶅ

Once

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