その提案はいい考えのように思われたが、彼らは断った。の英語

Although the proposal seemed like a good idea, they refused it.

Their proposal is full of holes.

You should have refused such an unfair proposal.

You should've rejected such an unfair proposal.

Such a proposal would only be turned down immediately.

I do not accept that proposal.

I will deny that proposal.

It is no wonder that you are turning down the proposal.

I'm sorry to tell you that your proposal has not been accepted.

I was unwilling to agree to the proposal, but it seemed that I had no choice.

it was a suggestion we couldn't refuse

It is highly regrettable that your request was considered to be unacceptable.

with scant regard to their suggestion

It has not yet decided whether to approve of your proposal.

It has not yet been decided whether to approve of your proposal.

For my part, I have no objection to the proposal.

My voice against the proposal was ignored.

Various innovative ideas were put forth at the meeting, but in the end, the most innocuous proposal was adopted.

It was sensible of you to refuse the proposal.＝You were sensible to refuse the proposal.

declined even to consider the idea

The proposition was not adopted―rejected.

someone who is resigned to defeat without offering positive suggestions

We are not likely to accept another offer any time soon.

I doubt the new proposal will be accepted.

My proposal was turned down in the conference.

Your suggestion seems irrelevant to our discussion here.

The proposal met with opposition.

They disregarded my objections to the proposal.

This proposal means it substantially opposes that.

The bishops were in favor of the proposition.