Tomme into giving up all plans for three weeks but he failed at last.A. tried to persuade

问题补充：

Tomme into giving up all plans for three weeks, but he failed at last.

A. tried to persuade

B. had tried to persuade

C. persuaded

D. had persuaded

答案：

A. tried to persuade

(答案→)B. had tried to persuade

C. persuaded

D. had persuaded

解析：考查时态和词组：try to persuade 尽力劝说，结果未知，强调动作； persuade 劝说（成功） ，强调结果。 根据句意，汤姆想说服我放弃三个星期的计划，但是最后失败了。从后面的but he failed at last.

可知主句应用过去完成时。选B。