0 needing skill or effort -- 困难的，费力的，艰难的
a difficult problem/choice/task/language 难题／艰难的选择／艰巨的任务／难学的语言
[ + to infinitive ] It will be very difficult to prove that they are guilty. 证明他们有罪将非常困难。
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。
[ + -ing verb ] It is extremely difficult being a single parent. 单亲家长生活非常艰辛。
[ + to infinitive ] The manager is difficult to deal with/a difficult person to deal with. 那位经理很难对付。
His wife is a very difficult woman. 他妻子是个难以接近的人。
mainly UK Please children, don't be so difficult! 孩子们，不要这样没规矩！
The noise outside made it difficult to concentrate.
It must be difficult to cope with three small children and a job.
She has had to make some very difficult decisions.
This novel is too difficult for intermediate students of English.
At the same time, adverbial licensing is a rather difficult topic, so some loose ends in the presentation can be expected.
At the same time, it was difficult, if not dangerous, to deny the developing sense of dominion identity.
From the 42 responses it was extremely difficult to distinguish between a protocol and an information sheet.
