In the trial, the accused party generally attempts to counter the elements of the article(s) of impeachment through arguments.
[1] After the articles are sent to the United States Senate, the Senate holds an impeachment trial on the charges of the article, sitting as the "High Court of Impeachment".
In such an instance, an official is already impeached and pending a trial even before the adoption of any articles to provide specific charges to be tried on.
[6] Often articles are created by a committee that has been tasked with running an impeachment inquiry.
In this instance, they are typically considered in a meeting called a "markup".