Can you bend your thumb backwards until it touches your wrist? If you join your hands behind your back, can you lift them over your head without letting go?
你是否能将大拇指向后弯曲直至其触碰到手腕部位？你将双手在背后紧握，是否能够将其举过头顶而不松手？
If you are building a bridge that is half completed, the customer is not going to say, "Gee, I think the bridge would be more useful at the next bend in the river rather than over here."
假设你正在建造一座桥梁，如果工程已经进行到一半，那么客户就决不会说：“天哪，我想这座桥要是建在河流的下一个弯口的话就更加实用了。”
If you ask her to help in the project, she is certain to bend over backwards to do whatever she can.
如果你请她帮忙搞这个工程，她肯定会竭尽全力地帮助你。
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