I forgot to tell you that...---Where is Mr.Black?---I forgot to tell you that he has gone to Beijing on business.还是 ---I forgot to tell you that he had gone to Beijing on business.
问题描述：
I forgot to tell you that...
---Where is Mr.Black?
---I forgot to tell you that he has gone to Beijing on business.
还是
---I forgot to tell you that he had gone to Beijing on business.
答
应该是：
I forgot to tell you that he has gone to Beijing for business.
但是既然两个都是on business的话，那就是第一个
因为gone不可以和过去式用在一起。
答
是第2个,在宾语从句中,主句是过去时,从句一定是过去时的某一种.
答
这是宾语从句,宾语从句的时态根据主句,
主句是过去时,所以,从句也是过去时
答案 第二句
布莱克先生在哪?
我忘记告诉你他去北京出差了.
答
是第二句 因为都是过去时 形式要一致