certainly

常用用法

certainly用于修飾動(dòng)詞,表示同意所陳述的事或確信某事是真實(shí)的。
certainly在句中的位置,如果有助動(dòng)詞(be, do, have等),一般放于助動(dòng)詞之后。如果表示否定,一般放于助動(dòng)詞之前。也可位于句首或句末,表示強(qiáng)調(diào)。
certainly作“當(dāng)然”解是非正式用語(yǔ),多見于口語(yǔ); 作“必定”解是正式用語(yǔ),口語(yǔ)和書面語(yǔ)均可使用。

這兩個(gè)詞的含義大不相同:
1.certainly表示有信心,很肯定; surely表示相信但又感到驚奇或難以相信。有surely的句子末尾常用問(wèn)號(hào)。例如:
Both of them played football better this time than they had done before, cer- tainly,Dick played splendidly.
他們倆這次比以往都踢得好,不用說(shuō), 迪克也踢得出色。
Surely that's a detective?
那人會(huì)是個(gè)偵探嗎?
2.certainly用于“的確知道真實(shí)情況”的場(chǎng)合; surely用于有一種強(qiáng)烈的愿望和信任感的場(chǎng)合。例如:
She is late, but certainly she will come.她遲到了,但一定會(huì)來(lái)。

這組詞(組)都有“確實(shí)地,一定地,當(dāng)然地”的意思。其區(qū)別是：
certainly可位于句首或句末,表示強(qiáng)調(diào),有時(shí)位于動(dòng)詞前,修飾全句,表示確有把握,深信不疑; of course通常用于表示自然的或不可避免的結(jié)果; for certain指確有把握,經(jīng)常用于否定句中。例如:
She certainly thought that this doctor was overestimating her case.
她確實(shí)認(rèn)為這醫(yī)生夸大了她的病情。
You could of course have criticized him, but,instead,you cried him down rudely.
你批評(píng)他當(dāng)然是可以的,可你卻粗暴地把他貶低。
I can't say for certain when he will arrive.
我說(shuō)不準(zhǔn)他什么時(shí)候到達(dá)。