由 Darren » 週一 4月 16, 2007 9:54 pm
I'm not very good at explaining grammar, so I'll try my best using palin terms:
Let's start with the first two sentences:
1: Tom who is jogging set fire on the house.
2: Tom who jogs set fire on the house.
Although these two sentences have the same main topic or information (Tom sets fire on the house), the additional informations on the other hand, are different. If you look at Sentence 1, it is actually a complex sentence where two plain statements are combined into one: "Tom sets fire on the house" (the main statement) and Tom is jogging (additional information). Punctuation wise (for easier read of sentence) would be something like this: Tom, who is jogging, sets fire on the house. Sentence 2, also a complex sentence, consist of two plain statements: "Tom sets fire on the house" and "Tom jogs". Again, punctuation for easier read would be: Tom, who jogs, sets fire on the house. If you read closely from above, These two sentences contain the same main information, but differ in the additinal information. S1 generally means: Tom sets fire on the house when he is jogging. In S2: Tom sets fire on the house. Tom jogs. This doesn't mean Tom was jogging when setting the house on fire.
Therefore, to answer your first question: Can we change both sentences into the sentence " Tom jogging set fire on the house."?
The answer will be NO.
Reason 1: two sentences have different information
Reason 2: " Tom jogging set fire on the house."? is grammatically incorrect.
To explain Reason 2 is another long paragraph. If you would like to read on, please do. If not, then just accept the fact that it would be grammatically incorrect.
Now, on to the explaination of Reason 2:
Becareful when writing a complex sentence. differentiate the two simple sentences out (phrases) when contructing a complex sentence. Each phrase must have its own appropriate verb and tense.
Let's analyse "Tom jogging sets fire on the house".
There are two phrases:
1: Tom jogging (extra informatin phrase)
2: Tom sets fire on the house. (main phrase)
**note** The reason we use complex sentences is to combine addtional information with the main information to make a piece of writing flow better when read. (provided that they have the same subject/doer of the sentence**end note**
A complex sentence combines two simple sentences, so that you don't have to write "Tom" twice. But then, you will need some extra punctuations. And, as mentioned before, the verb tenses must be correct as well. As you can seen from the above break-up of the complex sentence: Tom jogging isn't a proper simple sentence. You have to replace it with either "Tom jogs.", "Tom is jogging" or "Tom was jogging." etc etc. So when you combine the two simple sentence together into a complex one, the verb tense stays in the sentence:
"Tom, who is jogging, sets fire on the house."
or
"Tom, who jogs, sets fire on the house."
rather than writing two sentences: Tom jogs. Tom sets fire on the house.
The main point is: Make sure the verb tences are correct for each bit of information phrases. If you are not sure, start with simple sentences and keep their verb tenses while combining them into a complex sentence.
If you want others ways of saying "Tom, who is jogging, sets fire on the house", here's some other examples:
"Tom sets fire on the house while jogging."
or "While jogging, Tom sets fire on the house" (a bit contraversial on this one though)
or "Tom sets fire on the house when he was jogging" etc etc.
Cheers
