<<< native
[ ENumber "2"
, ENumber "5"
, EGrouped [ EIdentifier "y" , ESymbol Bin "+" , ENumber "3" ]
, EGrouped [ EIdentifier "x" , ESymbol Bin "+" , ENumber "3" ]
, EGrouped
    [ EIdentifier "x" , ESymbol Bin "+" , EIdentifier "\945" ]
, EArray
    [ AlignCenter , AlignCenter ]
    [ [ [ ENumber "2" ] , [ ENumber "3" ] ]
    , [ [ ENumber "4" ] , [ ENumber "5" ] ]
    ]
]
>>> mml
<?xml version='1.0' ?>
<math display="block" xmlns="http://www.w3.org/1998/Math/MathML">
  <mrow>
    <mn>2</mn>
    <mn>5</mn>
    <mrow>
      <mi>y</mi>
      <mo>+</mo>
      <mn>3</mn>
    </mrow>
    <mrow>
      <mi>x</mi>
      <mo>+</mo>
      <mn>3</mn>
    </mrow>
    <mrow>
      <mi>x</mi>
      <mo>+</mo>
      <mi>α</mi>
    </mrow>
    <mtable>
      <mtr>
        <mtd columnalign="center" style="text-align: center">
          <mn>2</mn>
        </mtd>
        <mtd columnalign="center" style="text-align: center">
          <mn>3</mn>
        </mtd>
      </mtr>
      <mtr>
        <mtd columnalign="center" style="text-align: center">
          <mn>4</mn>
        </mtd>
        <mtd columnalign="center" style="text-align: center">
          <mn>5</mn>
        </mtd>
      </mtr>
    </mtable>
  </mrow>
</math>