答案： I never thought he would succeed, would he?
解析：含有think, believe, suppose, imagine, expect等动词后接宾语从句构成的主从复合句在构成反意疑问句时,视情况不同有两种不同的构成方式.
(1)当主句的主语为第一人称时,其后的简短问句应与从句相一致.例如：
I expect our English teacher will be back this weekend, won't she/he?
I don't believe that he can translate this book, can he?
(2)当主句的主语为第二、三人称时,其后的简短问句则应与主句相一致（此时,否定只看主句,与从句无关）.例如：
Your sister supposes she needs no help, doesn't she? never和not都是否定词,只要主语是第一人称,就要否定转移.
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