adj.坏的；不好的；差的；疼痛的；严重的；有害的；腐败的；低劣的；不利的；不舒服的；不健康的
n.坏人；坏事
adv.非常；不好地
Smoking is bad for health. 吸烟对身体有害。
In the recession, our firm went through a bad time. 我们公司在经济衰退时期历尽艰辛。
He's gone to bad since he made friends with those people. 他结交那些人后就开始堕落了。
Their travel plan was cancelled because of the bad weather. 因为天气不好，他们的旅行计划取消了。
His shabby appearance creates a bad impression. 他那寒酸的样子给人留下不好的印象。
It's a very bad thing to leave things around. 把东西到处乱扔是很不好的习惯。
Bad eyesight is less common in this part. 这地区很少有视力差的人。
A bad workman quarrels with his tool. 手艺差的工人总是抱怨工具不好使。
I felt bad all day. 我整天觉得不舒服。
She's got a bad headache. 她头痛得厉害。
Leaving his name off the list was a bad slip-up. 名单上没有他的名字是个严重的疏忽。
It's bad to you to read in the sun. 在阳光下读书是有害的。
Stagflation is bad for stock market valuations. 滞涨对股票价值是有害的。
In several passages he stressed that bad governments, especially corrupt or repressive ones, could not expect his help. 在几页文字中，奥巴马强调，管理不善的政府，特别是腐败的或是镇压性的政府是不可能获得他的帮助的。
Pogroms, crusades, bad Popes, and crooked preachers on the Old Time Gospel hour have left a bad taste in many people's mouths. 大屠杀，十字军东征，腐败的天主教皇，和一些歪曲事实的布道者在旧时期给人们留下了太多的负面影响。
I thought it was a very bad article. 我以为那是一篇很低劣的文章。
They protested about the bad food. 他们对低劣的伙食提出了抗议。
The decadence of morals is bad for a nation. 道德的堕落对国家是不利的。
Your bad skin will tell against you if you want to be an actress. 如果你想当演员的话，你粗糙的皮肤对你是不利的。
Bad breath, as well as being unpleasant, can be interpreted by would-be lovers as a sign of health problems. 口气不清新或让人不舒服会被对方视为身体不健康的标志。
用作名词 (n.)He was for putting bad men behind bars. 他赞成将坏人关进监狱。
The bad man will suffer eternal damnation. 坏人将会受到永远的惩罚。
You must learn to take the bad with the good. 人必须学会好坏都能承受。
用作副词 (adv.)That's what I want, and I want it bad. 这就是我想要的，而且是迫不及待要得到的。
Alison sings bad. 艾莉森唱得很糟。
当badly用来修饰want，need或require时，指“很”，原来只是在口语中出现，现在文字中也较普遍。 She needs a new coat badly.她很需要一件新的外套。
feel bad同feel badly都表示“身体或精神上感觉不好”，有时指“因和别人感同身受而感觉不好”。feel badly在字面义上还可指“触觉不好”。
adj.(形容词)bad的基本意思是“坏的,邪恶的,不道德的”,也可作“令人不快的,使人讨厌的”“严重的; 显著的”“有病的”“有害于某人的”“不适宜的; 困难的”等解。
bad在句中可用作定语或表语。
bad和feel, seem, look等词连用,意为“不舒服”。
bad的比较级为worse,最高级为worst。
bad一般不用于否定句中,习语not bad的意思是“不错”。
bad在美国俚语(主要是黑人用语)中可作“顶呱呱的”“挺时髦的”解，此时的比较级为badder，最高级为baddest。
n.(名词)bad用作名词意思是“坏的事物”,引申可表示“厄运”。是不可数名词。
