关于“插入语”

Parenthesis is the addition of extra information to an already formed sentence. A parenthesis can be separated from the sentence with dashes, commas or brackets, and these are known as parentheses.



When the parenthesis is removed from the sentence, it should still be grammatically correct. So, to make sure that you have included a parenthesis correctly, reread the sentence to see if it makes sense without it. If it does, then you have successfully added a parenthesis.

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Follow the guidelines below to find out which parentheses you should use within English text.

• Commas – When using commas to separate parenthesis within a sentence they may get confused with the other ‘normal’ commas. However, the plus side for using commas with the parenthesis is that it will flow like a normal sentence.
  
• Dashes – Using dashes with the parenthesis makes it more obvious that it is extra information, which technically, makes it appear separate from the original sentence.
  
• Brackets – Again, using brackets makes the parenthesis easily visible to the reader. However, using brackets can sometimes make the text appear unorganised.
  

Here are some examples of parenthesis within a sentence. All three of the parentheses will be used in these examples; note that the parenthesis will appear in bold to make it easier to spot:

• Isabelle’s favourite toy - the wind up dog – is broken.
  
• During a midnight raid, which took place at the soft toy factory, a man was shot.
  
• Dawn Adler’s best friend (Jane Haughton-Smith) was arrested yesterday by armed police.
  
• The naughty dog, which chewed my shoes, is now living outside in a kennel.
  
• The bread, which I bought from the supermarket, has already gone stale.
  

Sometimes, when using parenthesis in a sentence, writers often forget to actually end the parenthesis. When you use a parenthesis in a sentence, think of it as using brackets; you wouldn’t leave brackets open, so remember not to leave a parenthesis open either.



Leaving a parenthesis open can cause confusion within the sentence, which makes it difficult for the reader to understand the original meaning.



All of the following words and phrases are classed as parenthesis within a sentence; however, they are not normally used with brackets or dashes, and are more likely to be used with commas.

• However
  
• As a result
  
• Therefore
  
• So to speak
  
• For all intents and purposes
  
• As far as I am concerned
  

Parenthesis is very common in the English language; using parenthesis and parentheses helps add more information to a statement without stopping the flow of the reading or writing.



The easiest way to see if you have added a parenthesis into a sentence is to see if the sentence can survive without the added information.

说得很对。

这个网址里也有比较详细地说到什么是插入语

http://www.howtolearnenglish.co.uk/english-language--what-parenthesis.html