I'm sure／I'm not sure

A high degree of conviction
degree「ディｸﾞﾘｰ」n,程度、学位　conviction「ｺﾝヴィｸｼｮﾝ」n,確信
I'm absolutely sure I filled them in.
I'm a hundred percent sure I did.
A moderate degree of conviction
moderate「ﾏｰﾀﾞﾚｯﾄ(米）　ﾓｰﾀﾞﾚｯﾄ（英）」adj, 中くらいの、適度の
I'm pretty sure I ordered them.
I'm fairly sure I said it was today.
fairly「フェｱﾘｲ」adv,公平に、正しく
A low degree of conviction
I'm not really sure. I'll have to check.
I'm not so sure I told her.
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A: I just had a call from HR. They were wondering if you’d sent the training reports.
(had sent: 過去完了)  HR:human resources 人事部
resource「リｿｰｽ」「ﾘソーｽ」 n,源、資源  natural resources 天然資源
B: Yeah, I sent them by courier on Tuesday morning.
They should be there by now.　今ごろ小包はそこに届いているよ。

courier「カｳﾘｱｰ」「クｳﾘｱｰ」n,小包
should be there そこにいるべき、そこにあるべき   by now 今ごろは
A: Ther haven't received them yet. Are you sure?
B: I'm pretty sure. Let me check if I have the receipt. Wait a minute.
I might have sent them to the Accounting department by mistake.
receipt 「ﾚスィ-ﾄ」n,レシート

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I'm pretty sure I emailed to my colleague.