XML one is something like that:

<dict>
    <key>2</key>
    <array>
        <string>A</string>
        <string>B</string>
    </array>
    <key>3</key>
    <array>
        <string>C</string>
        <string>D</string>
        <string>E</string>
    </array>
</dict>      

XML Two is something like that:

<dict>
    <key>A</key>
    <array>
        <string>A1</string>
        <false/>
        <false/>
        <array>
            <string>Apple</string>
            <string>This is an apple</string>
        </array>
        <array>
            <string>Apple Pie</string>
            <string>I love Apple Pie.</string>
        </array>
    </array>
    <key>B</key>
    <array>
        <string>B7</string>
        <false/>
        <false/>
        <array>
            <string>Boy</string>
            <string>I am a boy.</string>
        </array>
    </array>
</dict>

I want to convert to this:

<dict>
    <key>2</key>
    <array>
        <string>A, Apple, Apple Pie</string>
        <string>B, Boy</string>
    </array>
    ...
</dict>