certainly
/ˈsɜːtənlɪ/adverb
sentence adverb
1- used to convey the speaker's belief that what is said is true无疑; 确定地（用以表示说话者相信所言属实）：
the prestigious address certainly adds to the firm's appeal.
这个久负盛名的地址肯定会增强公司的吸引力。
1.1
- used to indicate that a statement is made as a concession or contrasted with another没错, 的确, 确实（如此）, 无可否认（用于表示让步或表示某一说法是另一说法的对照）：
our current revenues are certainly lower than anticipated.
我们现在的收益的确比预期的少。
1.2
- used to express complete agreement with something that has just been said确实如此（用于表示完全同意对方刚说过的话）：
'A good idea, ' she agreed. 'Certainly!'
“好主意,"她同意道, “确实如此！”