cer‧tain‧ly S1 W1 / sɜtnli $ sɜr- / 副词 [句子副词]

1 without any doubt 同义词 definitely :

I certainly never expected to become a writer.

They’re certainly not mine.

it is certainly true/possible etc

It is certainly true that there are more courses on offer.

The girl was almost certainly murdered.

‘Not smoking has made a real difference.’ ‘It most certainly has.’

2 spoken used to agree or give your permission :

‘I’d like a beer, please.’ ‘Certainly, sir.’

‘Can I come along?’ ‘Certainly.’

3 certainly not spoken used to disagree completely or to refuse to give permission :

‘May I go?’ ‘Certainly not!’

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In everyday English, people usually say of course or sure rather than certainly when agreeing or giving permission:

‘Can I sit down?’ ‘ Of course. ’

THESAURUS

certainly used when saying that you are sure about something : Amy’s certainly growing, but she’s not gaining weight. | It’s certainly not the cheapest way of getting to New York. | ‘Is this his signature?’ ‘Almost certainly.’

undoubtedly used when saying that you are completely sure about something. Undoubtedly sounds more certain and a little more formal than certainly : They are undoubtedly the better team. | Undoubtedly it will be a huge shock for him. | The furniture, although undoubtedly fashionable, was a little too plain for my taste.

there is no doubt used when you are completely sure about something : There is no doubt that violence on TV influences children. | He’s definitely innocent. There’s no doubt about that.

without (a) doubt used when you are completely sure about something : She was without doubt one of Mexico’s finest artists. | There would be, without a doubt, some perfectly ordinary explanation for his behaviour.