常常搞不清楚什么时候用过去式，例如以下这二段文章让我很困惑...
More battles follow,ending with the famous Battle of Agincourt. Henry's
forces are dramatically outnumbered, and he is worried because many of
his men are sick. He rouses his troops with an inspiring speech that
happens on the day of the Feast of St.Crispin. Referring to his soldiers,
Henry says......
虽是在讲过去的故事，但都是用现在式，但紧接着下面这段却是用过去式。
The French army was larger and better equipped,but the English army
had the heroic Henry leading it.
有人可以解释一下吗？为什么二段都是在讲过去的事，时态却不一样？？