Meaning of さぞかし in Japanese

Definition of さぞかし

さぞかし(sazokashi) 【嘸かし】

(adv) certainly; surely →Related words: 嘸 , 嘸や
こんなにすばらしい本を書くとは、著者はさぞかしりっぱな学者だろう。
What a good scholar the author must be to write such a splendid book!

Miyoko carried a torch so long, I think it gave her heartburn.

彼女かのじょは若いわかいときさぞかし美人びじんだったに違いないにちがいない。

She must have been a beauty when she was young.

Well done! Your parents must be proud of you.

You must be hungry to eat so much rice.

You must be very hungry now.

What a good scholar the author must be to write such a splendid book!