<SCRIPT LANGUAGE="JavaScript">
function disableForm1()
{
    if(document.FORM2.check.checked) {
        document.FORM2.select3.blur()
        document.FORM2.select3.disabled=false
        document.FORM2.select4.disabled=false
    } else {
        document.FORM2.select3.blur()
        document.FORM2.select3.disabled=true
        document.FORM2.select4.disabled=true
    }
}
</SCRIPT>

<FORM name="FORM2">
<INPUT TYPE="checkbox" NAME="check" onClick="disableForm1()">선택하기
<BR>

<SELECT NAME="select3" disabled>
<OPTION SELECTED>선택1
<OPTION>1-1</OPTION>
<OPTION>1-2</OPTION>
<OPTION>1-3</OPTION>
</SELECT>

<SELECT NAME="select4" disabled>
<OPTION SELECTED>선택2
<OPTION>2-1</OPTION>
<OPTION>2-2</OPTION>
<OPTION>2-3</OPTION>
</SELECT>
</FORM>