One of the stumbling blocks in the Doha round, for example, was "preference erosion".

举个例子，阻碍多哈会议进程的一个绊脚石就是“优惠侵蚀”。

youdao

So what are the stumbling blocks?

那么，障碍是什么呢？

youdao

So there are two stumbling blocks.

所以目前有两个主要的障碍。

youdao

Shanahan says one of the major stumbling blocks is the United States.

VOA: standard.2009.11.04

"There is a sense that when the political leaders arrive in the next few days, that they will be able to overcome some of the stumbling blocks, because I believe the leaders will be able to really grab this issue by the scruff of the neck and get down to the substance and bridge the remaining gaps,".

VOA: standard.2009.12.17

Even from that point, though, there are many stumbling blocks on the way to social progress.

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Yet the industry's record could be even more impressive, save for two stumbling blocks.

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He went on to tackle the major stumbling blocks in negotiations with Palestinians over the years.

BBC: Israel sets terms for Palestinian state