人教版九年級英語上冊《When was it invented?》SectionB PPT課件下載(第3課時)，共37頁。
Objectives
To summarize the passive voice of the past tense.
To think about your problem and think of the new invention to solve your problem.
To write a passage to describe your invention.
Revision
一般過去時被動語態
一般過去時的被動語態表示過去某一時刻發生的被動性動作, 其基本結構為：
主語+ was / were + 過去分詞+ by ...
►The teacher was visited by them two years ago.
他們兩年前看過這位老師。
主動變被動解題步驟:
1. 找賓語 ——即動作的承受者
2. 判斷賓語的單復數 ——即be動詞的單復數
3. 判斷動詞的時態 ——即be動詞的時態
4. 修改謂語的時態 ——即原句動詞改為過去分詞
5. 修改原句的主語 ——即by + 主語/ 賓語
Warming up
Inventions are everywhere in our life.
Imagine you are a business person. Write a description of your new invention. Try to sell the invention to the class.
This special pen was invented by Liu Jie.
It has three colors and is used for…
Sample writing
This special pen was invented by Liu Jie. It has three colors and is used for taking notes quickly. It is very useful if you have a lot to write down. The pen comes with a microchip that can store a list of common words that you will use. You can program the words you will use often into the microchip’s memory, then assign a short form to each word. When you are writing, you just need to write the short forms with the pen, press a button on the pen and the short forms will change into the actual words. The microchip can contain up to 50 words and you can make changes to the list of words whenever you need to.
Self check
Complete the passage with the correct form of the words in the box.
invent doubt mention website all of a sudden
It is often difficult to decide on the inventor of certain inventions. This is because sometimes a few people may ______ things which are nearly the same. It’s hard to tell who came up with the idea first.
Some inventions can also lead to other inventions ______________. So some people _________ whether the inventor came up with the idea himself or herself. They think that the inventor used someone else’s idea to create his or her invention. That is why books or ________ usually _________ more than one inventor when giving information about inventions.
Rewrite these sentences using the passive voice.
1. Someone stole my watch.
2. They used five eggs to make this big cake.
3. When did they invent the personal computer?
4. They asked us not to run in the hallway.
5. Someone took the video back to the store.
Homework
Write an article about your favourite invention.
Do some exercises about passive voice.
Preview the new words in the next unit.
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