synthesis

The second one is optional, and omitting it would avoid tiresome repetition. If you omitted the word "playing" altogether...

I prefer soccer to basketball.

...it would not be clear whether you meant you meant as a player or as a spectator.

If we're talking about spoken English here, the 2nd one is optional, and most people leave it off. But if you were to write a paper, or take the SAT or something, I would include it, since I think it's more proper.

Re: synthesis

No, the second "playing" is not optional. "I prefer playing soccer to basketball" means that the speaker prefers playing soccer to basketball in general, not to playing basketball.

Compare these sentences:

I like to watch my children. I like to watch sports more.

I prefer watching sports to my children.

That makes it sound like the speaker's children are less important to the speaker than watching sports. The parallel structure, therefore, must be maintained in order to avoid ambiguity or confusion.

joefromchicago, I think you just like finding posts to disagree with, on rather thin grounds sometimes. I find Porsches more fun to drive than Yugos. Are you telling me that in this sentence-

"I prefer driving Porsches to Yugos", I have to put the word "driving" before "Yugos" in order for the sentence to mean what I want it to?

The second instance of the verb is implied to most people.

I prefer drinking beer to water
I prefer watching French films to Hollywood ones.
I prefer eating beef to chicken.

Not so. There are many threads on this forum where I find myself in complete agreement with the other posters. Every so often, I even find myself in agreement with you. On those occasions, I rarely feel the need to add a "me too" post where the initial query has already been adequately addressed. It's only in those threads where I disagree with someone else's advice that I tend to get involved.


As I said previously, in order to avoid ambiguity or confusion, one should maintain the parallel sentence structure.


No doubt in many sentences that's true. That doesn't mean that it's necessarily right, just that it's acceptable to most people.

Could another member tell me what the correct answer should be? I'm quite confused.

Many thanks.

It is optional--but only because most native speakers of English will know that both soccor and basketball are games which one "plays."