配列をPHPのarray_merge、array_push、array_merge_recursiveを使ってマージした出力結果は以下の通りです。

array_merge マージ出力結果

Array ( [0] => A [1] => B [2] => C [3] => D [4] => E [5] => F )
Array ( [no] => 2 [sei] => suzuki [mei] => ziro [sex] => women [todofuken] => tokyo [city] => yokohama )

array_push マージ出力結果

Array ( [0] => A [1] => B [2] => C [3] => Array ( [0] => D [1] => E [2] => F ) )
Array ( [no] => 1 [sei] => yamada [mei] => taro [sex] => men [todofuken] => tokyo [0] => Array ( [no] => 2 [sei] => suzuki [mei] => ziro [sex] => women [city] => yokohama ) )

array_merge_recursive マージ出力結果

Array ( [0] => A [1] => B [2] => C [3] => D [4] => E [5] => F )
Array ( [no] => Array ( [0] => 1 [1] => 2 ) [sei] => Array ( [0] => yamada [1] => suzuki ) [mei] => Array ( [0] => taro [1] => ziro ) [sex] => Array ( [0] => men [1] => women ) [todofuken] => tokyo [city] => yokohama )