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- I can't say for certain when he will arrive. 我说不准他什么时候会来。
- I can't say for certain what to do. 我说不准该做什么。
- I couldn't say for certain when he'll arrive. 我说不准他什麽时候到。
- Certain prepositions usually follow certain nouns. 某些介詞通常跟隨某些名詞。
- For certain reasons I will be unable to attend the meeting. 因为某种原因，我不能出席这次会议。
- I can not say for certain what to do. 我说不准该做什么。
- I can't say for certain off-hand. 我还不能马上说定。
- Do you know for certain what will happen to him ? 你肯定他会碰到什么事吗?
- We never knew for certain how it happened. 究竟是怎么发生的，我们始终未搞清楚。
- Nobody knows for certain what kind of man he is -- he's rather a lone wolf. 谁也不知道他是什么样的一个人--他总爱独来独往。
- Look at that sky! It's going to rain for certain. 瞧那天空！肯定要下雨了。
- I can not say for certain when he will arrive. 我说不准他什么时候会来。
- He may succeed,but I don't know for certain. 他也许能成功，但我不敢肯定。
- We don't know for certain when it happened. 我们不能肯定是在什么时候发生的。
- We may succeed,but I can't know for certain. 我们可能成功，但我不敢说肯定成功。
- Harris says: "We can't say for certain. 哈里斯说：“我们说不准。
- I can't say for certain when we'll arrive. 我说不准我们什么时候能到。
- For everything, we can not have it for certain. 万事万物我们其实都不可能有绝。
- Adjusted sounds for certain objects. 将某些物体的声音进行了一些调整。
- I can't say for certain what my plans are. 我说不准我的打算是什么。
