一、介绍性说明文的写作步骤：
第一段：开头对要说明的事物或事情简要介绍(点题)
第二段：主提按照题目提供的信息分层次，按照一定的顺序进行说明，注意语言的客观简明。
第三段：结尾照应开头(题目没有特殊要求，不要对此事物发表看法)
二、常用的词句
1. 表达时间
1)a long time ago， 2) at six o’clock in the morning， 3)at the end of，
4)at the weekend， 5)before he came here， 6) by the end of last term，
7)during the summer holidays， 8)in a few years’ time， 9)in the past，
10)in the old days， 11)in the past ten years， 12) in August 2002，
13)in winter vacation， 14) in weekdays， 15) last month， 16) next week，
17)on Sunday morning， 18)on October 1st
19)since early in the 20th century， 20)so far， 21)up to now， 22) not…until， 23)while ， 24)in the 1930’s ( in the thirties of the twentieth century)
25)January， February， March ， April， May， June， July， August， September， October， November， December
2. 表达地点
1)at the crossing， 2) at the end of the street， 3)at the airport， at the village，
4)at the foot of the mountain， 5)at the bottom， 6)at the top of，
7) be located in， 8) behind the park， 9)be situated in，
10)five kilometers to the north of Guangzhou，
11)in the south of Guangdong Province， 12)in the middle of the park，
13)in Class 3 Grade 2， 14)in front of the bus， 15) in the tree，
16)in Guangdong， 17) in China，
18)lies to the west of Sichuan， 19)on the other side of the street，
20)on both sides of the road， 21) on the east coast of the Pacific Ocean ，
22)on the right。
3. 表达因果
as， as a result， because， because of， for， in the end， cause， result in， consequently， originate from， since， so， therefore， It is clear that… ， It turns out to be… ， The primary reason is … ， etc.
4. 常用指路句子
1)Go along the street and take the second turning on the left/turn left at the second crossing沿着这条街往前走，在第二个十字路口向左拐。
2)Cross the bridge/Go across the bridge.过桥
3)Go on until you reach the end. 一直往前走，直到尽头。
4)It’s about 100 meters along on the right. 它就在前面靠右大约100米处。
5)Go along the street until you come to the traffic lights. 沿这条路一直走到红绿灯那儿。
6)Turn right / left at the second crossing. (Take the second turning on the right / left.) 在第二个十字路口向右 / 左转弯。
7)Take a number 46 bus， and get off at the square. 坐46路公共汽车，在广场下车。
8)It‘s on the corner of Huaihai Street and Xizang Road. 在淮海路和西藏路的路口。
9)Go straight ahead along the bund and then turn left. 沿着外滩往前走，然后往走转弯。
10)It’s only about ten minutes‘ walk. (D) 那儿离这儿只有走大约10分钟的路。
My home is not far from here. It’s only five minutes walk. 我家离这儿不远，走5分钟就到。
It is one hour’ ride from Shanghai to Suzhou. 从上海坐车到苏州有1小时的路程。
三、段落练习
1.这所中学是20世纪60年代建立的。全校目前有21个班，121位老师和1，031名学生。学生每天上七节课，放学后还有一小时的体育活动时间。该校的足球队是全市的冠军。
2.我的家乡是一个小镇。它位于河北的西部，天津的南面。虽然它很小但很漂亮。以前它很穷，现在发生了很大的变化。这里盖了许多新的工厂，学校和医院。路旁的树木和鲜花使得它显得很美丽。
3.我们的教学楼是一栋四层的楼房。老师的办公室在一层。二、三、四层共有24个教室。每个教室中有50套桌椅，一台电视机和一台录像机等物品。每层楼的顶端还各有一个语音教室。
4.金鸡牌闹钟(Gold Cock Alarm Clock)特点： 1)记时准确;2)外形多样、美观;3)闹声清脆悦耳; 4)经久耐用;5)用户评价高、行销世界各地;6)质优价廉。
Possible version：
1.This school was set up in the 1960s. At present there are 21 classes， 1，031 students and 121 teachers in the school. The students have seven lessons every day and they have an hour for sports after class in the afternoon.。 This school is famous for its football team， which is the champion in the city.
2.My hometown is a small one. It lies in the west of Hebei and to the south of Tianjin. Small as it is， it‘s very beautiful. It used to be very poor. Now great changes have taken place in my hometown. A lot of new factories， schools and hospitals have been set up. There are many flowers and trees on the roadside， which makes my hometown. all the more beautiful.
3.Our teaching building is a four-storeyed building.(Our teaching building is a building with four stories.) The teachers’ offices are on the first floor. There are 24 classrooms on the 2nd，3rd， and 4th floor. In each classroom there are 50 sets of chairs and desks. And each classroom is furnished with a TV set 。 At the end of each floor there is a language laboratory.
4.The Gold Cock Alarm Clock has been warmly received by the people and is popular all over the world as its producer is equipped with(装备) the most advanced equipment and has a strict management. Being of high quality， the clock keeps good time and lasts a long time. It has various beautiful models. And the alarm is pleasant to hear. However， the price is reasonable.