1.逗号：
(1). 在句子里面用于并列的词语之间.如：
Id you keep calm, tak eyour time, concentrate and think ahead, you’ll pass your drinving test.
假如你保持镇定、不慌不忙、集中精力注意前方,驾驶考试就能及格.
(2). 常用于主句与状语从句或较长的词组之间.如：
When a policyholder has a loss, he or she asks for payment from the insurance company. 当投保人遭受损失后,他们要求保险公司支付损失.
(3).用于在句首非限定的或无动词的短语之后.如：
Discoved in 1789 and isolated from other elements in 1841, uranium is valued as a source of atomic enegy.
铀于1789年被发现,1841年被从其他元素中分离出来,它被珍视为原子能的一个来源.
(4). 用以将引导性词语或转折性词语(如there fore, however, by the way, for instance, on the contrary)与句子的其余部分隔开.
如：In the United States, for example, nodding your hand up and down means“yes”. In the same parts of Green and Turkey, hower, this motion can mean”no’.
比如在美国,点头表示“是”或“可以”,而在希腊和土耳其的某些地区,这一动作却表示“不行”.
(5).用于插入句中的从句等成分的前后.如：
Every individual cell, whether it exists as an independent microorganism or is part of a complex creature, has its own life circle.
每个单独的细胞,不论它是作为一个独立的微生物而存在,还是作为一个复杂生物的一部分而存在,都有自己的生命周期.
(6). 用于非限定性定语从句或同位短语前后,进一步说明前面的名词或句子.如：
The painter lived more than a decade in Europe, where he could be in close contact with other cubists.
(7).有时用以分隔并列复合句(尤指较长的),用于连词(如and ,as,but,for,or)之前.如：
The fragrances of many natural substances comes from oils, and this oils may be used in manufacturing perfumes.
许多自然物质的香味来自油类,因此,这样的油可以用来生产香水.
(8). 用以将附加疑问句或类似词语与句中其余部分隔开.如：
He is an excellent scholar, isn’t he? 他是位优秀的学者,是吗?
(9). 在直接引语中作者提示“某某说”之类的词语(如he said, she told, etc.)用逗号与引用语分开.如：
“This house is very big an dbeautiful”said Fritz.“这所房子又大又漂亮,”弗里茨说.
(10). 引语里面的引语用逗号隔开.如：
“When the Judge said,‘Not guilty’, I could have hugged him.”
“当法官宣布,‘无罪’,我当时真想去拥抱他.”
(11). 用于表示日期.如：May 1, 2003 2003年五月一日
2.and：
conjunction
used to connect words of the same part of speech, clauses, or sentences, that are to be taken jointly
[用来连接同词性词、分句和句子]和,与
bread and butter.
面包和黄油.
red and black tiles.
红色与黑色的瓷砖.
they can read and write.
他们能读和写.
a hundred and fifty.
一百五十.
■used to connect two clauses when the second refers to something that happens after the first
[用来连接两个分句,后一分句指后发生的事]然后
he turned round and walked out.
他转过身然后走了出去.
■used to connect two clauses, the second of which refers to something that results from the first
[用来连接两个分句,后一分句指前一分句引起的结果]因此,结果
do that once more and I'll skin you alive.
再那么做,我要活剥你的皮.
■connecting two identical comparatives, to emphasize a progressive change
[连接两个相同的比较级来强调一渐进的变化]越来越
getting better and better.
变得越来越好.
■connecting two identical words, implying great duration or great extent
[连接两个相同的词,暗示连续或程度]接连,又
I cried and cried.
我哭了又哭.
■used to connect two identical words to indicate that things of the same name or class have different qualities
[用来连接两个相同的词表示同一事物有不同性质]此外还有
all human conduct is determined or caused—but there are causes and causes.
所有人类行为都是先决的或有原因的——但有这样那样的原因.
■used to connect two numbers to indicate that they are being added together
[用来连接两个数字表示相加]加
six and four makes ten.
6加4等于10.
■(archaic)used to connect two numbers, implying succession
(古)[用来连接两个数字,含有连续之意]两个两个地
a line of men marching two and two.
一列两个人并排行进的队伍.
used to introduce an additional comment or interjection
[用来引导补充说明或插入语]并且
if it came to a choice—and this was the worst thing—she would turn her back on her parents.
如果要做出选择─这是最糟的事——她会背弃她父母的.
■used to introduce a question in connection with what someone else has just said
[用来引导和某个人刚说的话有关的问题]那么,接着
‘I found the letter in her bag.’ ‘And did you steam it open?’.
“我在她包里发现了信.”“那你用蒸汽拆开信了?”.
■(especially in broadcasting) used to introduce a statement about a new topic
[尤在播音中引导和新话题有关的话]那么,接着
and now to the dessert.
现在来谈甜食.
(informal)used after some verbs and before another verb to indicate intention, instead of ‘to’
(非正式)[用于某些动词后和另一动词前表示目的,取代“to” ]以,来. 见后面 usage
I would try and do what he said.
我会力图照他说的去做.
