1. 我不确定,但我认为这件事还应该多加讨论。 I'm not sure, but I think it need more discussion.
2. 我不太肯定,但我记得期末考试是在下个周一早晨。 I'm not sure ,but I remember the examination is on next monday' morning
3. 我不太确定,但我想我们可以跟老板再讲讲价。 I'm not sure, but I think we can ... with the boss.