知識
作者：
（一）
Dear Mr. Green
I work in the Friendship Shop on Zhongshan Road 1.________
where you have often come to buy things. The other day 2.________
if you bought a vase at our shop with your wife， I made 3.________
the mistake about the price. You looked at two different 4.________
price of the same vase， one costing 30 yuan and the other 5.________
21 yuan. You took the 21 yuan one so I accepted 30 6.________
yuan from you. I found my mistake only after you and 7.________
your wife have left. Will you please come to our shop to 8.________
get in your change or to return your vase and get a 30 9.________
yuan one instead？ I apologize you for it. 10.________
I’m looking forward to your coming earlier.
Yours truly，
Wang Hua
（二）
In many western countries heavy industry is high developed 1.________
The difference between heavy and light industry are based on 2.________
the nature of the goods produced. Heavy industry produce 3.________
machines while light industry uses machines produce the 4.________
smaller objects required for various purpose in our home 5.________
and offices.
The growth of industry in country depends on the 6.________