Itrainedhardyesterday,______preventedmefromgoingtothepark.
A、thatB
本句话为非限制性定语从句，所以不能用 that 来引导。在本题中， prevent 由于是行为动词，所以正确选项应为 B。
Iftheoperation________carefullyprepared,itwouldnothavebeensuccessful.
Not until recently_____that Thompson had ben telling the truth all along.
支持代孕的理由有
Hewas______towithdrawfromrunningforthepresidency.
Itisnousearguing_______theplanbecauseithasbeenrejected.
