define width and height inside ur html.

eg. find "img" tag, then define width and height

< i m g w i d t h="77" h e i g h t ="77" src="http://urimage" border= 0 >

or u may click "编辑助手" button when u post ur posts.
before sending ur posts out, u may preview ur posts, if u click 测试 button in the "加贴编辑助手" window.

good luck~