In the horizontal radiobutton options, usually the first label of options is located in the right of the first option. Is possible the first label located in the left of the first option, thus more fit with our reading habits? For example, "stronely agree 5 4 3 2 1 strongly disagree" rather than "5 stronely agree 4 3 2 1 strongly disagree". Thanks so much!

No. You would have to omit labels entirely from the <radiobuttons> /options and use separately positioned <caption> elements to display them at the desired locations.

Dear Dave, thanks so much for your quick reply! Do you mean I need omit the labels firstly and then use separate caption located above the number option? This kind of display looks like a real paper-back questionnaire, right? Thanks again!

Yes, something like that. You can find an example for something similar at e.g. http://www.millisecond.com/forums/Topic1847.aspx#1847.

Sounds wonderful. I am trying. Many  thanks, Dave!