[TYPO3] Rich Text Editor: how to move text up as shown in the typo3 tutorial video?

[Bing Du]

Hi,

Typo3 V4.0.4
rtehtmlarea 1.3.8

I've seen the video 'Insert Images In The Rich Text Editor' a few times. 
But I was not able to move up the text to wrap the image as the video did.
 I clicked the 'Justity left' icon in the tool var.  But the text stays
unchanged.  I know as a workaround, I can use text w/ image type option
'In text, left'.  But we also need to insert images directly in RTE.  Now
that it works in video, I don't understand what I did wrong that it didn't
work for me.

Thanks in advance for any help,

Bing