【would've VS wouldn't have】肯定文と否定文イントネーションの違い

We would’ve been able to make it /wi woo duv bin nei bul tu mei kit/ 「（〜だったら）出来ていただろう」 We wouldn’t have been able to make it /wi woo dun nuv bin nei bul tu mei kit/ 「（〜だったら）出来ていなかっただろう」 It could’ve been worse  /i koo duv bin wers/ 「不幸中の幸いだった」 It couldn’t have been better  /i koo dun nuv bin be ter/ 「最高だった」 I should’ve been more careful /ai shu duv bin mor keir ful/ 「もっと気をつければよかった」 You shouldn’t have been there /yu shu dun nuv bin their/ 「あなたは行くべきじゃなかった」 I would’ve come if I had known you were there. I wouldn’t have come if I had know you were there. Thank god, you are safe! It could’ve been worse. The show was awesome. It couldn’t have been better. I should’ve bought it before it’s sold out. I shouldn’t have bought it without knowing well.