by accident 偶然
on account of 因為,由于
in addition 另外
in the air 在流行中,在傳播中
on (the /an) average 平均,一般來說
on the basis of 根據(jù),在…基礎上
at (the) best 充其量,至多
for the better 好轉(zhuǎn),改善
on board 在船 (車、飛機)上
out of breath 喘不過氣來
on business 因公,因事
in any case 無論如何,總之
in case of 假使,萬一
in case 假如,以防(萬一),免得
in no case 決不
by chance 偶然,碰巧
in charge (of) 負責,主管
(a)round the clock 晝夜不停的
in common 共用,共有,共同
in conclusion 最后,總之
on condition that 在…條件下
in confidence 信任
in connection with/to 關于
in consequence 因此,結(jié)果
in consequence of 由于…的緣故
on the contrary 反之,正相反
in contrast with/to 與…成對照
out of control 失去控制
under control 被控制住
at all costs 不惜任何代價
at the cost of 以…為代價