美国白宫：8月1日的关税截止日期实际上只是一个开始的日期，标志着美国将开始从总统已寄出信件的所有国家收取这笔收入。你们在8月1日之前可能会看到一些更多的信件，也可能会有更多的贸易公告。

Group 1 - The core point of the article is that the White House has indicated that the tariff deadline of August 1 is merely a starting point for the collection of tariffs from all countries mentioned in the letters sent by the President [1] Group 2 - The article suggests that more letters and trade announcements may be expected before the August 1 deadline [1]