481. once and for all =once and forever永远地
all at once (=suddenly, now) 立即,马上
once in a while (=occasionally) 偶尔
(just) for once 就这一次
482. (all) by oneself 独自(没有别人帮助)
483. operate on sb. 给某人做手术
operation n. come/ go into operation开始运转
put/bring sth. into operation 使…投产,运转
484. be of the opinion 持有…的看法
485. in one’s opinion 按某人的看法
486. be opposed to… 反对…
487. be opposite to 与…相反的
488. (be) in order(=acceptable)合适的,恰当的
in order 井井有条,处于良好状态; out of order(=in bad condition)出毛病,发生故障
489. made to order 定做的(衣服)
490. originate in/from(=begin)起源于,由..引起
491. on the outskirts (of) 在城郊
492. owe…to 把…归于…
493. on one’s own (=along, without help)单独
494. of one’s own某人自己的
495. keep pace with 跟…齐步前进
496. go to great pains=take pains 下功夫,努力
497. part with (=give up, sell) 舍弃,卖掉
498. participate in (=take part in)参加
499. (be) particular about 讲究,挑剔(吃,穿)
500. in particular (=especially) 特别是,尤其