This page, my images have problem again, it should be showed with small size in order and then click to show big ones. but now some errors happened. please help! this kind situation happened before. Thanks
Since we don’t know which sizes you wanted to use as thumbnails and which sizes you wanted to be clickable, it’s difficult to help you.
Let me ask a general question. Under Dashboard->Settings->Writing have you selected “WordPress should correct invalidly nested XHTML”? If not, you should do that. Then go back and edit that page again, making any change; it doesn’t matter what. Just add a space or something, then Update. That might help.