Sentence with relative/participle clauses and noun/prepositional phrases

[Chicken Sandwich]

Complete the sentence by adding the pieces of information given. Use relative clauses, additonal noun phrases and participle clauses and prepositional phrases.
[...]
4. The conference...
(The conference was held in Singapore. It approved the world trade agreement. The agreement was drawn up by European and Asian states. The conference whas now ended.)
(Advanced Grammar in Use, Martin Hewings)

My sentence is different from the one provided by the book:

The conference, which was held in Singapore and has now ended, approved the world trade agreement, which was drawn up by European and Asian states.

The book suggests:

The conference (held) in Singapore, which approved the world trade agreement drawn up by European and Asian states, has now ended.

Does my sentence also work? At first I thought that it was OK, but now it looks as though using "which" twice doesn't really work. Also, I'm not quite sure about my use of commas :-?.

Thank you in advance.

 

[SoothingDave]

Re: Writing relative/participle clauses and noun/prepositional phrases

I like your focus better cause the main action is the approval of the agreement, and not the conference ending.

I would lose the final comma and the "which was." "...trade agreement drawn up by..."

I would replace "which was held in Singapore and has now ended" with "which has now ended in Singapore."

 

[Chicken Sandwich]

Re: Writing relative/participle clauses and noun/prepositional phrases

Thanks, ShootingDave. I like your version, which only contains one "which".

The conference, which has now ended in Singapore, approved the world trade agreement drawn up by European and Asian states.

One unwanted implication of your version might be that the conference began somewhere else, even though it ended in Singapore. But perhaps that's just my reading ;-).