0 needing skill or effort -- 困难的，费力的，艰难的
mainly UK Please children, don't be so difficult! 孩子们，不要这样没规矩！
His wife is a very difficult woman. 他妻子是个难以接近的人。
[ + to infinitive ] The manager is difficult to deal with/a difficult person to deal with. 那位经理很难对付。
[ + -ing verb ] It is extremely difficult being a single parent. 单亲家长生活非常艰辛。
Many things make it difficult for women to reach the top in US business. 有很多因素使女性难以进入美国商界的上层。
[ + to infinitive ] It will be very difficult to prove that they are guilty. 证明他们有罪将非常困难。
a difficult problem/choice/task/language 难题／艰难的选择／艰巨的任务／难学的语言
The category differences correspond to different morphosyntactic properties, but the semantic values of these words are difficult to differentiate.
In these the heterogeneity is difficult to interpret.
As some of these forces are acting on this population, it is difficult to make any estimate on this result.
In some ways, the code examples make it a little difficult to jump around, since you are expected to build upon previous code.
Combined with the lack of an overview or common examples this makes it quite difficult to compare the four languages.
Their system proves fewer program transformations as equalities, requiring instead the more difficult notion of observational equivalence.
We find it difficult to introduce these optimisations in our model and at the same time to keep the correctness argument simple.
Without a sufficiently rich belief system it is difficult for subjective measures to accurately model the user domain.
