Skywriting 。

People began writing message in the sky many years ago.挥毫云霄间，多年前就有人开始在天空留言了

Ninety years ago, people attending the English Derby watched in awe as a message appeared in the sky. White smoke spelled out "Daily Mail." the name of a local newspaper. The smoke had come from a plane flown by pilot Cyril Turner. He was performing a complex series of maneuvers above the racetrack, releasing smoke to spell the words.

Years earlier, British air force officer John C. Savage had developed this technique, called skywriting. Savage's  intention had been to create a way of sending messages in an emergency. His idea came from his experience during World War I when low-flying planes released smoke to block the enemy's vision. Later in 1992, the same year as Turner's flight, American pilot Allen J. Cameron introduced skywriting to America. He wrote "Hello USA" in the sky above New York City.

Many companies including Pepsi recognized skywriting's potential. From the early 1930s until the 1950s, Pepsi used skywriting more than any other company as its primary means of advertising.  Today, some companies still advertise through skywriting from time to time, but skywriting has also acquired a more personal use. One New York Skywriting company puts more than 50 marriage proposals in the sky each year.

Grammar  Tips:
Today, some companies still advertise through skywriting from time to time.
"from time to time" - occasionally, not regularly.
Wendy's mother would let her go play in a local park from time to time.
I like to shop at that store from time to time.
"From time to time" -Something happen again and again in occasionally.
"period" - from what time to what time, we call "period" not "time to time".

Vocabulary Tips:
intention- want to...意图，用意。
*My intention was to help out, but it was misunderstood.
*I have no intention to change my career. I'm happy with my job. 没想要。。。
*It wasn't my intention to harm you.
potential -潜力，潜能。
*I think your business has a lot of potential.
*Nina has great dancing potential, but she needs formal training.
potential -潜在的可能。。
*potential customers.
acquire - get it, obtain. 获得，取得。
*He spent a lot of money remodeling his newly acquired apartment.
acquire -学到。
*Renee acquired French while she was living in Paris.
Derby- a professional horse race.
awe - it's awesome, so cool, wah! amazed.
maneuver - a serial of movements that require some skill and practice.  ab act or movement repeat.
technique - the way of deal or do.
proposal - man ask women to marry him. or idea, suggestion 提案， 求婚。.

Chat Room:
The smoke had come from a plane flown by pilot Cyril Turner.
flown - fly 的过去式
fly by- flown by.
fly by -由他驾驶，开飞机，(n): 飞机低空飞行，战机的空中分列式表演。
fly-by-night : 靠不住的，不能信赖的，不负责任的。原本指“夜间潜逃的负债人或是在金钱上不负责任的人。。make a lot of money over night, and suddenly disappeared. (fly away)
fly-by-night company.- 在金钱上不负责任公司，潜逃消失找不到了。



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