明确：词是构成短语或句子的语言单位，作为词，必须兼顾最小的和自由运用的条件，二者缺一不可;短语是由词和词组合而成的语言单位，是构成句子的基础，它不仅可以充当各种句子成分，而且大多数短语带上一定的语气、语调，就成为一个句子;句子是语言的'使用单位，它是由短语或单个的词构成的，一个句子可由一个短语充当，也可由一个词充当。
一、词与短语的区别
1.根据语音来区分。词的内部各语素之间语音上一般是连续的，也就是说语素之间没有停顿，如艰苦卓绝的斗争就是由四个词构成，艰与苦、卓与绝、斗与争之间不能停顿;短语的内部成分之间在语音上大多是停顿的，如雄伟壮丽、聪明漂亮等，中间都可以停顿，所以是短语。
2.根据意义来区分。一般来说，词的意义有整体性，即它的意义不是它的语素意义的简单相加，如苦瓜是指一种蔬菜，而不是苦和瓜的意义相加;可短语的意义就不同了，它一般是由组成短语的几个词的意义相加，如思想感情是思想和感情的意思相加。
3.用扩展法来区分。即在两个音节之间插入成分，插入后意义不变的是短语，意义交了或不能插入的是词。如联合式的组合可插入连词来检验，聪明伶俐可扩展为聪明和伶俐，所以聪明伶俐是短语，而壮观等组合不能插入连词，所以是词。
二、短语和句子的区别
1.句子有语调，句终加标点。如看书!因为有了!号，所以标志着这是个句子，如果去掉!，就变成一个动宾短语了。
2.句子具有表达性，能表达一个完整的意思，完成一项简单的交际任务。如他哭了!短语不具备这个特点。
(一)定义
句子是表示相对完整的意义，前后都有停顿，带有一定语调，人们用来进行交际的基本语言单位。书面上以句号、问号或叹号来表示停顿和语调。如：
我想喝水!
全句语调趋降，下降幅度较大，是感叹语气。
(二)句子与词、短语的区别
词和词可以构成短语，词和短语都是结构单位，而句子不是从结构，而是从使用角度划分出来的。换句话说，词和短语是备用单位，句子是使用单位;词和短语是静态单位，句子是动态单位;词和短语之间是组合关系，词、短语同句子之间是实现关系。
1.两者的差别是质的区别
词和短语同句子的区别，并不在于量，而在于质。量再少，哪怕是一个词，只要带上语调，就是一个句子。如：
"水!"在不同语境，有不同意思。当病人迷迷糊糊地躺在床上，嘴里轻轻地说，意思是"我要喝水"。当军队在漆黑的山沟里急行军，走在前面的战士突然地喊了一声，意思是"这里有水，注意不要踩上去"。当一行人在沙漠里迷路，走了好几天，又干又渴，走在前面的忽然大声说，意思是"我们终于找到水了"。
量再大，哪怕十几个词，甚至是几十个词，可能还是短语。如：
"必须进一步巩固和发展中俄两国之间面向二十一世纪的新型伙伴关系"述宾短语，在"双方一致认为必须进一步巩固和发展中俄两国之间面向二十一世纪的新型伙伴关系"中只是一个句法成分。只有它带上语调，进入某一语境使用时，才实现为句子。
同样道理，句子不一定是主谓短语。主谓短语也可能只是句中一个成分，如：
主谓短语"他喜欢打球"在"我知道他喜欢打球"中只作宾语。
2.句子结构复杂度与语境依赖度成反比
词和短语实现为句子时，对语境的.依赖度同其本身结构的复杂性呈反比。语言单位越简单，对语境的依赖性就越大。语言单位越完备，对语境的依赖性就越小，它的多义性就越少。如：
a、水。
b、喝水。
c、想喝水。
d、我想喝水。
e、我想喝一杯水。
学生写作时，要使文章耐人寻味，有深度，应尝试使用一些高级词汇或句型，下面就一起来看看英语写作提分的诀窍有哪些吧
英语写作提分的诀窍
1、灵活改变句子开头
在通常情况下，英语句子的排列方式为“主语+谓语+宾语”，即主语位于句子开头。但若根据情况适当改变句子的开头方式，比如使用倒状语或以状语开头等，会使文章增强表现力。
· You can do it well only in this way.
→ Only in this way can you do it well.
只有这样你才能把它做好。
· A young woman sat by the window.
→ By the window sat a young woman.
窗户边坐着一个年轻妇女。
2、避免重复使用词语
为了使表达更生动，更富表现力，同学们在写作时应尽量避免重复使用同一词语来表示同一意思，尤其是一些老生常谈的词语。如有的同学一看到“喜欢”二字，就会立刻想起like，事实上，英语中表示类似意思的词和短语很多，如 love, enjoy, prefer, appreciate, be fond of, care for等。
· I like reading while my brother likes watching television.
→ I like reading while my brother enjoys watching television.
我喜欢看书，而我的兄弟却喜欢看电视。
3、合理使用省略句
合理恰当地使用省略句，不仅可以使文章精练、简洁，而且会使文章更具文采和可读性。
· He may be busy. If he’s busy, I’ll call later. If he is not busy, can I see him now?
→ He may be busy. If so, I’ll call later. If not, can I see him now?
他可能很忙，要是这样，我以后再来拜访。要是不忙，我现在可以见他吗?
· If the weather is fine, we’ll go. If it is not fine, we’ll not go.
→ If the weather is fine, we’ll go. If not, not.
如果天气好，我们就去;如果天气不好，我们就不去了。
· She could have applied for that job, but she didn’t do so.
→ She could have applied for that job, but she didn’t.
她本可申请这份工作的，但她没有。
4、运用非谓语结构
非谓语结构通常被认为是一种高级结构，适当运用非谓语结构，会给人一种熟练驾驭语言的印象。
· When he heard the news, they all jumped for joy.
→ Hearing the news, they all jumped for joy.
听了这消息他们都高兴得跳了起来。
· As I didn’t know her address, I wasn’t able to get in touch with her.
→ Not knowing her address, I wasn’t able to get in touch with her.
由于不知道她的地址，我没法和她联系。
5、结合使用长、短句
在英语写作中，过多地使用长句或过多地使用短句都不好。正确的做法是，根据实际情况在文章中交替使用长句与短语，使文章显得错落有致，这样不仅使文章在形式上增加美感，而且使文章读起来铿锵有力。
At noon we had a picnic lunch in the sunshine. Then we had a short rest. Then we began to play happily. We sang and danced. Some told stories. Some played chess.
→ At noon we had a picnic lunch in the sunshine. After a short rest, we had great fun singing and dancing, telling jokes and playing chess.
中午我们晒着太阳吃野餐。休息一会儿后，我们唱的唱歌，跳的跳舞，还有的'讲笑话、下棋，大家玩得很开心。
6、使用短语代替单词
· He has decided to be a teacher when he grows up.
→ He has made up his mind to be a teacher when he grows up.
他已决定长大了当老师。
· He doesn't like music.
→ He doesn't care much for music.
他不大喜欢音乐。
· He told me that the question was now under discussion.
→ He told me that the question was now being discussed.
他告诉我问题现正正在讨论中。
7、套用某些固定表达
· He was very tired. He couldn’t walk any farther.
→ He was too tired to walk any farther.
他太累了，不能再往前走了。
· The film was very interesting. Both the teachers and the students liked it.
→ The film was so interesting that both the teachers and the students liked it.
这电影很有趣，学生和老师都很喜欢。
· Your son is old. He can look after himself now.
→ Your son is old enough to look after himself now.
你的儿子已经长大，可以自己照顾自己了。
8、使用地道英语
· Don't worry. Be bold and try it, and you'll learn it soon.
→Don't worry. Just go for it, and you'll get it soon.
别担心，大胆试一试，你很快就会学会的。
· Thank you for playing with us.
→Thank you for sharing the time with us.
谢谢你陪我玩。
9、综合使用“高级”结构
· We had to stand there to catch the offender.
→ What we had to do was (to) stand there, trying to catch the offender.
我们所能做的只是站在那儿，设法抓住违章者。
· If her pronunciation is not better than her teacher’s, it is at least as good as her teacher’s.
→ Her pronunciation is as good as, if not better than, her teacher’s.
如果她的语音不比她的老师好的话，至少也不会比她老师的差。
10、引用
在写作时根据实际情况恰当地用上一两句名言警句来点缀文章，不仅使文章显得有深度、有智慧，而且会让文章在评分中上一个“得分档次”。
· As the proverb says, “Where there is a will, there is a way.” Though you fail this time, you needn’t lose heart. As long as you work hard and stick to your dream, you will succeed one day.
· There is a proverb goes like this “Life isn’t a bed of roses.” It is ture that it is likely for everyone to meet problems and difficulties in life.
· In the modern world, more and more people live alone, which is not so good for our life. It is better for us to make more friends and enjoy friendship. Just as a proverb says, “A near friend is better than a far-dwelling kinsman.”
