>>670
英語のネイティブです。標準英語ではこういう文章は古臭くて言いませんね。方言だと可能ですけど。動詞はbeでなくtake、spendなどにすればいいです。

△　You will be a month learning them.
〇　You will *spend* a month learning them.

△　He was not five minutes repairing it.
〇　It did not take him even five minutes to repair it.