I am sorry (to hear) that.为什么添to hear?

i am sorry to hear that.是什么意思? I am very sorry to hear that. 关于I am sorry to hear that i'm sorry (to hear)that为什么填to hear i am sorry to hear that that you said I am sorry to hear tha i am sorry to hear that 这个句子中,请问 to hear that 做什么成分 that I am to hear sorry.(连词成句） I am sorry to hear that you resorted ______. i am so sorry to hear that.so 是什么词性. I am sorry to hear that怎么解释? i am sorry to hear that 什么意思 I am sorry to hear that you resorted ___