This plan need not be expensive, but it faces one big difficulty.

这项计划花费不大，但却面临一个很大的难题。

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For these rural children, strength isn't a problem, but etiquette is a big difficulty.

对于这些来自农村的孩子，体力不是问题，礼仪方面的学习却是个难题。

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Southern margin of Junggar basin is characterized by abundant hydrocarbon resources and multiple traps, with low degree of prospecting and big difficulty for exploration.

准噶尔盆地南缘油气资源丰富，圈闭众多，勘探程度低，难度大，是盆地最现实的油气勘探战略接替区。

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Language is another big difficulty.

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But, she notes, he might have sympathised with her over one big problem: the surprising difficulty of changing medical routine.

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But his difficulty in giving that big speech on Europe in about a week's time is what if he's wrong on any one of those ifs?

BBC: David Cameron says there will be EU referendum if...