People didn't look at me quite as much as they had yesterday

1。quite是程度副词,在此句中表示对as much as的程度上的修饰,更多时候只表示说话人一种强调的语气,不需要加以翻译。
2。they had yesterday中的had是过去完成时had looked at me的缩写。
因为是比较写法,所以前面出现的动词短语在后面无须全部写出。
如：I play soccer as well as you do。
此句中的助动词do即前面的play soccer的缩写。