sublime text添加snippet

下面的${1:this}格式的会在tab键下一次切换选中

<snippet>
    <content><![CDATA[Hello, ${1:this} is a ${2:snippet}.]]></content>
    <!-- Optional: Set a tabTrigger to define how to trigger the snippet -->
    <tabTrigger>--</tabTrigger>
    <!-- Optional: Set a scope to limit where the snippet will trigger -->
    <!-- <scope>source.python</scope> -->
</snippet>