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- The teacher set his pupils a difficult problem. 老师给学生出了一道难题。
- It's a difficult problem and I should like to go over the ground again. 这个问题是很麻烦，我想再了解一下情况。
- How to quiet title is still a difficult problem. 如何决定所有权仍然是一个困难问题。
- In itself, it's not a difficult problem to solve. 这本身并不是个难解决的问题。
- It's really a difficult problem. 我们该怎么办。
- We found it a difficult problem. 我们发现这是一个难题。
- We have a difficult problem to solve. 我们有一个难题要解决。
- Never have I come across such a difficult problem. 我还从没有遇到过这样困难的问题。
- A difficult problem or two occupied his mind. 有一两个困难问题在他心里回旋。
- A difficult problem or question. 难题，令人费解的问题
- To present a difficult problem to; puzzle. 难住使面对一个难题
- She is working at a difficult problem in mathematics. 她在做一道数学难题。
- This is a difficult problem,yet to be adequately resolved. 这是一个难题，有待充分解决。
- Eyelet phenomenon is a difficult problem in Image recognition. :图像识别是计算机应用领域中的前沿技术 ,小内孔现象是导致识别率低的主要因素之一。
- Such a difficult problem is it that no one can work it out. 这道题如此之难,以致没有一个人能算得出来。
- It is such a difficult problem that none of us can work it out. 这个问题太难了以致于没有人能够做出来。
- It's an old problem, a big problem and a difficult problem. 一个老问题,一个大问题,也是一个难问题。
- How to grow rice in such a dry area is a difficult problem. 在这样干旱的地区种水稻可是一个难题。
- This is such a difficult problem as nobody can work it out. 这道题太难了,没有人能解出来。
- It's worthwhile taking the trouble to explain a job fully to new employees. 给新雇员详细解释一下工作要求，费点事也是值得的。
