unforgettable，memorable，indelibility ；

[例句] 明亮的流星，或者说陨石，是番难忘的景象。 A bright shooting star, or meteor, is an unforgettable sight.

[例句] 约翰的魄力和热情最令人难忘。 John will be best remembered for his drive and enthusiasm.

[医] difficult labour，dystocia，mogitocia，parodynia；

[例句] 每年有50万女性难产致死是本可避免的。 Half a million women die needlessly each year during childbirth.

[例句] 与头胎不同, 这次是难产. This time , unlike the first, the birth was an ordeal.

hard to avoid，be booked for ；

[例句] 家家有本难念的经，也都难免互生嫉妒，但总归血浓于水。 Families have their problems and jealousies, but blood is thicker than water.

[例句] 做人权工作是要冒风险的。这是难免的。 Doing human rights work is risky business. That comes with the territory.

difficult problem，a hard nut to crack，aporia，poser，conundrum ；

[例句] 把英镑与欧洲其他货币合并会引发许多难题。 Integrating the pound with other European currencies could cause difficulties.

[例句] 即便是聪明人在面对难题时也未必就能表现得特别聪明。 Even clever people are not terribly clever when put on the spot.

suffer calamities or disasters，be in distress，suffering ；

[例句] 他的受审重新勾起了在战争中受苦受难的法国人民的回忆。 His trial revived memories of French suffering during the war.

[例句] 我们长期受苦受难的采矿群体应该得到比这更好的待遇。 Our long-suffering mining communities deserve better than this.

danger and disaster，calamity，jeopardy ；

[例句] 危难造成了一种患难与共的精神. The difficulties have created a spirit of togetherness.

[例句] 这次危难是对他的勇气和技能的考验. The crisis put his courage and skill to the test.

hardness，knotty，abstruseness，abstrusity ；

[例句] 令人难解的是, 他竟一直保持沈默. Unaccountably, he kept silent.

[例句] 脚注阐明了文中难解的段落. Footnotes illuminated the difficult passages of the text.

ashamed，embarrassed，find it difficult，disconcerting ；

[例句] 你觉得她曾为此而难为情吗？ Do you think she was embarrassed about it?

[例句] 实话实说让男人觉得难为情。 Men find it embarrassing to be honest.

difficult to ；

[例句] 我们得到了通常难以获取的大量数据。 We gained a rich supply of data which would normally be inaccessible.

[例句] 他经历的恐怖事件在他脑海中刻下了深深的，或许是难以磨灭的印记。 The horrors he experienced are imprinted, perhaps indelibly, in his brain.

difficult to comprehend，hard to understand ；

[例句] 她的诗在风格上是时髦的实验派，主题艰深难懂。 Her poems are modishly experi-mental in style and recondite in subject-matter.

[例句] 这说明书看起来很难懂。 The instructions look very complicated.

aporia，difficult point，difficulty，nodus，rub ；

[例句] 英语句法的难点 the difficulties of English syntax

[例句] 这是谈判中主要的难点之一。 This was one of the major sticking points in the negotiations.

botchy，malformed，rebarbative，shameful，grotty ；

[例句] 多难看的东西啊，扔掉，扔掉。 What ugly things; throw them away, throw them away.

[例句] 山坡上有幢难看的灰色大房子。 Above on the hillside was a large, gaunt, grey house.

meet with a catastrophe ；

[例句] 那些汽车堵住出口能把这地方变成遭难场所. The cars blocking the exits could turn this place into a death - trap.

[例句] 这使她去帮助世上受苦遭难的人. This drives her to help anyone who suffers anywhere in the world.

unintelligible，mysterious，abstruse，cramp，enigmatical ；

[例句] 令人难解的是, 他竟一直保持沈默. Unaccountably, he kept silent.

[例句] 脚注阐明了文中难解的段落. Footnotes illuminated the difficult passages of the text.

impatience，intolerability ；

[例句] 场面非常刺激撩人，我感到欲火难耐。 It was extremely hot and I was feeling rather randy.

[例句] 接近华氏100度的高温让他们感觉酷热难耐。 They sweltered in temperatures rising to a hundred degrees.

difficulty，a hard nut to crack，a piece of work，tickler，twister ；

[例句] 改善家庭能耗并非难事。 It doesn't take much to improve the energy efficiency of your home.

[例句] [谚]世上无难事,只怕有心人. Nothing is difficult to a man who wills.

pose，stump ；

[例句] 我承认我一度被难住了。 I admit I was foxed for some time.

[例句] 她紧张地咽了一下, 似乎那问题把她难住了. She gulped nervously, as if the question bothered her.

unruliness，intractability ；

[例句] 汽车的功率越大，就越难驾驭。 The more powerful the car the more difficult it is to handle.

[例句] 很多人认为这是最难驾驭的领域. Many believe this is the trickiest area to navigate.

afflictive，trying，fierce ；

[例句] 世上最让人难受的莫过于小婴儿遭到遗弃。 The saddest thing in the world is a little baby nobody wants.

[例句] 这对他是一段非常难受的经历. It had been a most trying experience for him.

catastrophe ；

[例句] 上周的霜冻对柑橘种植业是一场大灾难. The frost last week was a great calamity to the citrus industry.

[例句] 洪水是一场大灾难. The flood was a major catastrophe.