REPORTED SPEECH

"leave"的過去式或發詞都是"left". 不論前面is 還是was都是這樣，沒有甚麼好轉．　且left在句中是被動，一定要用left (剩下的意思）．
I leave a child here.
The child is left by me.
left over (剩下的食物（廚餘））
left behind （被遺下的人）
　　

首先你要知道在轉reported speech時，你的句字已經轉了時式，由there is nothing ......轉為there was nothing......（注意：這個there不是解作那裏，是解作存有，或有，所以there's nothing要譯作沒有，而不是那裏沒有）
至於left是leave的過去分詞，而不論現在分詞也好，過去分詞也好，都可以作形容詞用，示句中的left也是過去詞作形容詞用。
如：Once there lived a man named John.這句的named也是用作形容詞分詞用，而整句可看為：Once there lived a man who was named John
同樣道理，你的示句，也可以看作there was nothing left for......=there was nothing that was left for.....
既然left是分詞用作形容詞用，所以我們索性就看它為形容詞吧！因此它並不需要轉成had left等等，希望你明白！

actually, the tense in Nancy's reply has changed already....watch it carefully.
Nancy actually has changed the tense from 現在被動式 to 過去被動式!!
in the question she used 'there'S nothing LEFT'---the tense she used "is left"
and then in her reply, she said 'there WAS nothing LEFT'--- the tense she used "was left"

so when you read these sentences, the individual 'LEFT' doesn't present the tense...'is/was left' should be the complete tense!!

因為0係LEFT之前隱藏左個that