Testing 'table rules=groups'. There should only be rules around each row group and column group in the tables below.

Table 1. Column groups
Test: Rules should only separate column GROUPS. There should be NO rules between the first two columns or the last two columns.

Column group 1 Column group 1 Column group 2 Column group 2

Table 2. Row groups
Test: Rules should only separate row GROUPS. There should be NO rules between the rows inside THEAD, TBODY, or TFOOT.

THEAD
THEAD
TFOOT
TFOOT
TBODY
TBODY