The phrase "advertisement before" is not correct and lacks clarity in written English.
It may be intended to refer to an advertisement that appears prior to something else, but it needs additional context to be meaningful.
Example: "The advertisement before the movie started captured everyone's attention."
Alternatives: "ad prior to" or "advertisement preceding".
Doing so almost always costs money, so be sure to carefully consider who is likely to view or hear your advertisement before agreeing to pay for advertising space or time.
The authority, which must approve advertising in the transit system, said it had not made a final decision on the advertisement before the lawsuit was filed.
Apple's iTunes has proved that some people do pay for music, and some will watch an advertisement before seeing an online video.
In return the producers agreed to include a short advertisement before the start of the film promoting Spain by the award-winning Spanish director Julio Medem.
Mr. Bush's chief media consultant, Mark McKinnon, said he had not noticed the word "rats" when he reviewed the advertisement before it was broadcast.
Mr. Gilligan did not mention the impending finale next Sunday, but he did not have to — the award was a free advertisement before an anticipated audience of at least 10 million viewers.
Eventually an agreement was reached requiring skiers to remove any advertisements before being photographed or interviewed.
It would also restrict corporations and labor unions from running issue advertisements before an election.
(Mr. Obama bought half-hour advertisements before a World Series game Wednesday night).
Rather, he decided to bring a preëmptive lawsuit objecting to the ban on issue advertisements before elections.
Eventually an agreement was reached that required skiers to remove any advertisements before being photographed or interviewed.
