两个英语句子动词形式的填写,求指教啊

两个英语句子动词形式的填写,求指教啊

As a child,I was scared of the dark.My older brother____(warn) me that there were monsters living in the basement,and I believed him.

When I asked for a day off in order to visit my son in college,my boss told me that it wouldn't be possible.This was not the first time he_____(be) so inflexible.

两个句子我都直接写了一般过去时,结构都错了= =
到底该用什么形式?如果能系统的讲解下,什么时候该用这种形式,那就更好了.

两个句子都用过去完成时,分别是：had warned,had been
第一个句当中,I believed him,我相信了他,是过去发生的,而我哥哥警告我则发生在我相信他之前,所以是“过去的过去”,这就需要用过去完成时.
第二个句子中,“This is/was +第几次”这个结构后面的从句需要用完成时,即is对应现在完成时,was对应过去完成时.可以这样理计算出第几次的时候,所计算的事情已经发生,所以是完成时.如：
This is the third time I have been in Shanghai.（这已经是我第三次到上海了.）