语法没学好，求指导~

When they got home, Jane cooked their dinner in the microwave oven and without realizing it, cooked her fiance's wallet as well.
" [# g" f3 g2 b0 r% }7 n" ~4 p9 c8 o3 L1 ^这句话的语法结构有谁能帮我分析下，特别是后面一个逗号的用法