1. sure, certain, positive, definite
2. reliable, trustworthy, safe, sound, firm, accurate, correct, exact
3. If I'm not mistaken, If I remember correctly, If I remember rightly
1. to think, to consider, to believe, to reckon
2. to think (of doing), to plan (to do)
3. to judge, to assess, to regard
4. to imagine, to suppose, to dream
5. to expect, to look forward to
6. to feel, to be (in a state of mind), to desire, to want
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