[析]by仅仅与交通工具相连表示应用某种工具，而加了别的修饰词后其前面的介词也应作相应的转换。如：by car (坐小汽车)by taxi (坐出租车)by bike (骑自行车)by water (乘船)by air (乘飞机)by sea (乘船)

　　[误]Mary began to learn how to play piano when she was three.

　　[正]Mary began to learn how to play the piano when she was three.

　　[析]在乐器前要加定冠词，而在球类游戏之前则不要加冠词，如：They like to play bridge when they are free. (他们空闲时爱打桥牌)

　　[误]The little boy wanted to go to cinema.

　　[正]The little boy wanted to go to the cinema.

　　[析]英语中虽有一些名词与go to连用时不加定冠词，以表示该名词的内涵，如：go to school (上学)，go to bed(睡觉)等，但去看电影则例外，要用go to the cinema.这也是语言的一个特点。

　　[误]I live at 105 the Lake street.

　　[正]I live at 105 Lake Street.

　　[析]街道名称前不用冠词。

　　[误]Next summer holiday I will go to country to live on a farm.

　　[正]Next summer holiday I will go to the country to live on a farm.

　　[析]country既作国家讲也作乡村讲。作乡村讲时，一定要加定冠词，而且只有单数形式，作国家讲时则可有复数形式。如：Japan is a country .Japan, China, India are Asian countries.

　　[误]The picture looks better at the distance.

　　[正]The picture looks better at a distance.

　　[析]at a distance意为“离开一定距离”。而in the distance为“远方，远处”。这样常用的词组有：

　　as a rule (照例)

　　in a hurry (匆忙)

　　in the morning/afternoon (上/下午)

　　in the sun (在阳光下)

　　in the rain (雨中)

　　in the same way (同样)

　　in the shade (在阴凉处)

　　in the day time (白天)

　　in the end (终)

　　on the other hand (换句话说)

　　on the contrary (相反)

　　[误]The little boy and girl walk along the street a hand in a hand.

　　[正]The little boy and girl walk along the street hand in hand.

　　[析]这是英语中的习惯用法，如：

　　bit by bit (逐渐)

　　day after (by) day (一天又一天)

　　day and night (日日夜夜)

　　face to face (面对面)

　　from A to Z (自始至终)

　　from time to time (再三)

　　hand in hand (手拉手)

　　shoulder by shoulder (肩并肩)

　　(三) 例题解析

　　1 Mr Li is___ old worker.

　　A a B an C some D /

　　[答案]B.

　　[析]an用于元音音素开始的单词前。

　　2 English is___ useful language in ___ world.

　　A an, the B a, the C the, / D /,the

　　[答案]B.

　　[析]因useful的第一个音素是[j]，它是辅音音素。

　　3 What ___ interesting book it is?

　　A a B an C the D /

　　[答案]B.

　　[析]这是感叹句，因为移到原一般句前面的强调部分中有可数名词book,所以应加冠词，而interesting的第一音素是元音所以要加an。

　　4 He will be back in ___ hour.

　　A / B the C a D an

　　[答案]D.

　　[析]因hour的首字母h不发音。

　　5 There is ___ map in the classroom. ___ map is on the wall.

　　A a, A B the, The C a, The D the ,A

　　[答案]C.

　　[析]在文章中首次提到某人或某物时用不定冠词，而第二次再提到该物或人时应用定冠词。

　　6 Look at___ picture! There's___ house in it.

　　A a ,a B the, the C a, the D the, a

　　[答案]D.

　　[析]虽然是第一次提到，但在句中的语言是让对方看某一特定的图画，所以应选择D。

　　7 There is ___ orange in the bottle.

　　A a B an C the D /

　　[答案]D.

　　[析]这里的orange是指桔汁而不是一个个的桔子。

　　8 Beijing is ___ capital of our country.

　　A the B an C / D a

　　[答案]A.

　　[析]capital之后有of结构则要用定冠词。

　　9 If you work hard at English, you'll get ___ “A” in the test.

　　A an B / C the D a

　　[答案]A.

　　[析]因字母A的第一音素是元音。

　　10 He usually goes to school on ___ foot.

　　A a B an C the D /

　　[答案]D.

　　[析]on foot意为走路上学，是习惯用法。