what充分的成分是什么

When you told Mrs. Bennet this morning that if you ever resolved on quitting Netherfield you should be gone in five minutes, you meant it to be a sort of panegyric, of compliment to yourself -- and yet what is there so very laudable in a precipitance which must leave very necessary business undone, and can be of no real advantage to yourself or any one else?"

你今天早上告诉Mrs.Bennet，说你要是下定决心离开Netherfield，五分钟之内就能搬走，你这话无非就是夸耀自己，恭维自己——不过，急躁轻率必定会弄得该做的事情没做成，无论对人对己都没有好处，又有什么值得夸耀的呢？

请教老师几个问题：

1、it可以指代前面出现的单词，也可以指代前

面任意句子的内容吗，比如这里you meant it to be...中的it就是指代前面if you ever resolved on quitting Netherfield you should be gone in five minutes这个主从复合句吗？

2、what is there so very laudable...，what充当这个句子的什么成分？

谢谢老师！