How many yards did Stephen Gostkowski gain on his first two field goals measuring 30 yards or shorter?
return Stephen Gostkowski ;return field goals of #1 ;return yards  of #2 ;return #2 where #3 is at most 30 yards ;return the  first two of #4 ;return yards  of #5 ;return sum of #6
['select', 'project', 'project', 'comparative', 'project', 'project', 'aggregate']