certain

音標['sә:tәn]　

中文翻譯：

a. 確定的, 某一個的, 必然的
【法】確鑿的, 無疑的, 可靠的
相關詞組:
be certain of
It is certain that
I am certain that...
I am not certain whether...
to a certain extent
for certain

例句：

For certain reasons I will be unable to attend the meeting.
因為某種原因，我不能出席這次會議。
I can't say for certain when he will arrive.
我說不準他什麼時候會來。
It's certain that every effect must have a cause.
無疑，每個結果必定有其原因。

字典網

英文解釋：

形容詞 certain:

definite but not specified or identified
having or feeling no doubt or uncertainty; confident and assured
同義詞：sure
established beyond doubt or question; definitely known
certain to occur; destined or inevitable
同義詞：sure
established irrevocably
同義詞：sealed
reliable in operation or effect
同義詞：sure
exercising or taking care great enough to bring assurance
同義詞：sure

詞意辨析：

sure, certain, definite, positive

這些形容詞均含“無疑的，確信的”之意。
sure: 側重主觀上對某事確信無疑。
certain: 與sure同義，但語氣比sure強，著重指有確切理由或不容置疑的證據所支持的確信。
definite: 指已毫無懷疑的餘地。
positive: 語氣強烈，指對自己的看法或作的結論的正確性有不可動搖的信念。