hard/ hɒːd /

1.adjective [+surface] [ object] 
(not soft) 硬的

the hard wooden floor
硬木地板
2.adjective [+question] [ problem] 
(not easy) 困难的

That is a very hard question to answer.
那个问题很难回答。
3.adjective [+work] 
费力的

Their work is hard and dangerous.
他们的工作既费力又危险。
4.adjective [+life] [ time] 
艰辛的

He's had a very hard life.
他的生活很艰难。
5.adjective [+push] [ punch] [ kick] 
(violent) 用力的

6.adjective [+person] [ expression] 
(severe) 苛刻的

7.adjective [化] [+water] 
硬的

8.adjective [+winter] [ frost] 
(cold) 寒冷的

9.adverb [work] [ try] [ think+] 
努力地

I've been working hard all day.
我已努力地工作了一整天。
10.adverb [laugh] [ rain] [ snow+] 
猛烈地

I've never seen Terry laugh so hard.
我从没见过特里笑得那么厉害。
The wind is blowing hard.
风猛烈地刮着。
11.adverb [hit] [ punch] [ kick+] 
(violently) 用力地

it is hard to understand what is happening
很难理解现在发生了什么事情
it's hard to tell/say/know
很难讲/说/知道
such events are hard to understand
这种事很难理解
to be hard to please
难以取悦
to find it hard to do sth
觉得做某事困难
it's hard work serving in a shop
商店工作很难做
hard luck!
真倒霉!
to be hard on sb
 [person+] 对某人过分严厉
12.adverb [situation+] 
对某人来说有害

no hard feelings!
别记仇!
to be hard of hearing
听力不佳
to feel hard done by
 [BRIT] 觉得受到不公平待遇
hard evidence/facts
铁证/客观的事实
be hard put {or} pushed to do sth
难以做某事
to look hard at
 [+person] 盯着
13.adverb [+idea] [ problem] [ situation] 
(consider) 认真考虑