It will take about four hours to defrost.

　　解凍要花四小時(shí)左右。

　　I should imagine it will take about three hours.

　　我想得用差不多三個(gè)小時(shí)吧。

　　I would imagine the job will take about two days.

　　我猜想這工作大概需要兩天左右的時(shí)間吧。