I run into trouble recent when use QGridLayout

This is my mainwindow. A QTabWidget, and add two QWidget tabs.
Tab use QGridLayout to arrange some labels.


The label can drop, and show after accept text.
But when text is too long, label stretch as same as text's length. I'm very worry, I want to fix proportion of each label's width and height. I try to set wordWrap true. But failed.


How can I do that?
My english is poor, so maybe it's difficult to understand, sorry!