In order to put ～と思おもいます(I think that～) after the speaker's conjecture (たぶん) ～でしょう(probably ～), replace でしょう with だろう.
*For nonpast affirmative na-adjectives and nouns, drop the だ ending of the plain form.
来年はたぶん物価が上がるだろうと思います。
I think that prices will probably go up next year.
雪国の生活はきびしいだろうと思います。
I think that life in the snow country is probably tough.
日本語でレポートを書くのは大変だろうと思います。
I think it is probably hard to write reports in Japanese.
Lesson 9-1「小林さんは今日はたぶんじゅぎょうを休むでしょう。」
Mr./Ms. Kobayashi will probably be absent from class today.
