分析句子"i was witness to events of a less peaceful character.One day when i went out to my..

分析句子"i was witness to events of a less peaceful character.One day when i went out to my..
"i was witness to events of a less peaceful character.One day when i went out to my woodpile,or rather my pile of stumps,i observed two large ants,the one red,the other much larger,nearly half an inch long,and black,fiercely contending with one another."
=====Herny David Thoreau
1.i was witness(这里不是被动吗.为什么不是witnessed?） 但是如果是名词,表示目击者为什么不用,i was a witness?
2.i was witness of events of a less peaceful character.One day i went out to my woodpile,or rather my pile of stumps,(这里为什么是or rather?直接是or my pile of stumps不就行了吗?rather在这里表示什么意思,在给我一个例句.）
3.one day when i went out to my woodpile ,or rather my pile of stumps,（我觉得这里应该加and,不是句子之间的连接吗,可是原文没有给and) i observed two large ants,the red one,the other much larger,nearly half an inch long,and black,fiecely contending with one other.(这里为什这么多的逗号,逗号的句子怎么写,能在举个例子吗?）