为什么英语的句子前面加'and'.告诉下.谢谢了..(详细点)

连词 conj. 和；加
together with;joined to;added to
· Look at that horse and cart.
瞧那匹马和马车。
· My father and mother are school teachers.
我的父亲和母亲都是学校老师。
· Two and two are four.
二加二等于四。


连词 conj. 连接两个动词
connecting two verbs
· We danced and sang.
我们又跳舞又唱歌。


连词 conj. 连接句子
connecting sentences
· He came and then he went.
他来了而后又走了。


连词 conj. 表示结果
showing a consequence
· He stood up, and all were silent.
他站了起来，于是大家都静了下来。
· Say that again and I'll hit you.
你要再说一遍，我就揍你。


连词 conj. 与‘去、来、送’等词连用表示目的
with go, come, send, showing purpose
· Come and see us.
来看我们。
· Try and move it.
试着移动它。


连词 conj. 用以强调增加或重复的
used to emphasize addition or repetition
· We ran and ran.
我们跑了又跑。
· again and again
反复
· dates and days
好多天
· every now and then
时而，不时
· farther and farther
越来越远
· miles and miles
许多英里
· over and over
重复；一遍又一遍
· repeat and repeat
一遍又一遍
· roll and roll
滚呀滚的
· think and think
想了又想

什麽意思 你能擧个例子吗？

and 作为连接词,可以表示对话题的补充说明,或进一步解释.有时候可以省略.I have finished the work,and I want my payment now.我已经完成工作了,现在就要工钱.I had made a mistake,and I feel soory indeed.我弄错...

一般来说是为了连接前句，造成比较有语调的氛围