You can say that you are going to recap when you want to draw people's attention to the fact that you are going to repeat the main points of an explanation, argument, or description, as a summary of it.
例句
To recap briefly, an agreement negotiated to cut the budget deficit was rejected 10 days ago...簡要概括起來，一項關于削減預算赤字的協議在10天前遭到了否決。Can you recap the points included in the regional conference proposal?你能扼要說明一下地區會議上提案的重點嗎？
英漢詞典釋義
vt. & vi.
扼要重述;概括
Recapped the headlines at the end of the news broadcast.在新聞的最后把主要內容概述一下。
英英詞典釋義
Noun
1. a summary at the end that repeats the substance of a longer discussion
2. a used automobile tire that has been remolded to give it new treads