of course 當(dāng)然，自然
That was 40 years ago,but of course you wouldn't remember it.那是40年以前的事了姿骏，你自然想不起來了。
off duty 下班
A policeman does not wear uniform while off duty.警察不上班時(shí)一般不穿制服抽莱。
on account of 因?yàn)椋捎?/p>
He could not come on account of his illness.他因病不能來骄恶。
on average 通常食铐，平均
On average babies start wakling at a year old.嬰兒一般都是在一歲時(shí)開始走路的。
on hehalf of 代表僧鲁，為了
He spoke on behalf of all staffs of the company.他代表公司所有員工講話虐呻。
on board 在船上
As soon as I'm on board I always feel sick.我一到船上，就總感到惡心寞秃。
on duty 值班斟叼，上班
All but me are not on duty.除我一人外全部不上班。
on earth 究竟春寿，到底
Where on earth have you been just now?剛才你到底上哪兒去了朗涩？
on foot 步行，徒步
She always goes home on foot.她總是步行回家绑改。
on guard 警惕谢床，站崗
The action of the thief soon put the policeman on guard.那小偷的行動(dòng)很快使警察們警惕起來。
on purpose 故意地厘线，有意地
It is not likely that he did it on purpose.他不可能是故意做那件事的识腿。
on the contrary 正相反，反之
You think me idle,but on the contranry I am very busy.你認(rèn)為我沒有事做造壮，但恰恰相反渡讼，我很忙。
on sale 出售费薄，減價(jià)售出
I got this hat on sale;it was very cheap.我在大減價(jià)時(shí)買到這頂帽子硝全，價(jià)錢很便宜。
on the one hand....on the other hand....一方面....另一方面....
On the one hand,it's cheap,but on the other hand,the quality is poor.一方面楞抡，它很便宜伟众，但從另一這方面來說，它質(zhì)量很差召廷。
on the spot 當(dāng)場凳厢，在現(xiàn)場
The news of important events is often broadcast on the spot over television.重要新聞經(jīng)常是通過電視在現(xiàn)場播出。
on the whole 總的看來竞慢，大體上
I think,on the whole,we had better stay at home.我認(rèn)為先紫，總的看來，我們還是待在家里為好筹煮。
on time 準(zhǔn)時(shí)遮精，按時(shí)，及時(shí)
You must go to school on time.你必須按時(shí)上學(xué)。
once again 再一次
The teacher asked John to read once again.老師讓約翰再讀一次本冲。
once in a while 偶爾准脂，有時(shí)
They go for a picnic in the park once in a while.他們偶爾到公園去野餐。
once more 再一次檬洞，又一次
Tom's back home once more.湯姆再一次回家了狸膏。
once upon a time 從前
Once upon a time there was a poor wood cutter who lived in the forest.從前樹林里住著一個(gè)貧窮的樵夫。
one another 互相
The members of the team support one another.球隊(duì)成員互相支持添怔。
or else 要不然湾戳，否則
Hurry up or else you'll be late.快點(diǎn)，否則你要遲到了广料。
or so 大約砾脑，左右
I shall return in a week or so.我大約一星期后就回來。
other than 除了....之外
No person other than a cook will be fit.除了廚師之外沒有人是合適的艾杏。
out of 缺乏拦止，用完；離開
He rushed out of the house.他從房子里奔了出來糜颠。
out of breath 上氣不接下氣，氣喘吁吁
The little boy ran out of breath.小男孩跑得上氣不接下氣萧求。
out of order 混亂其兴，發(fā)生故障
My watch is out of order. What time is it?我的表出了毛病。幾點(diǎn)鐘了夸政？
out of sight 在看不見的地方
They waved to one another till the train was out of sight.他們互相揮手直到火車消失在遠(yuǎn)方元旬。
out of the question 毫無可能的，辦不到的守问。
In the absence of political independence,economic independence is out of the question.沒有政治上的獨(dú)立匀归，就談不上經(jīng)濟(jì)上的獨(dú)立。
over and over again 反復(fù)地耗帕，再三地
His father warned him over and over again.他的父親三番五次地警告他穆端。
owing to 由于，因?yàn)?/p>
Owing to his laziness, he failed in the test.由于他的懶惰仿便，他沒有通過這次考試体啰。
