s:if test#it.count % 3 0/trtr/s:ifs:if test#it.count % 3 0/trtr/s:if
<s:if test='#it.count % 3 == 0'></tr><tr></s:if>
<s:if test='#it.count % 3 == 0'></tr><tr></s:if>
<s:if test='#it.count % 3 == 0'></tr><tr></s:if>
<s:if test='#it.count % 3 == 0'></tr><tr></s:if>