//仅选择JavaScript
//selected = $('#para-1');
//仅选择Erlang
//selected = $('.color-red.color-green');
//选择JavaScript和Erlang
//selected = $('.color-red');
//选择所有编程语言
//selected = $('.color-red,#para-2.color-green,.color-black[name="name"]');
//selected = $('p[class^="color-"]');
//选择名字input
//selected = $('input[name="name"]');
//选择邮件和名字input
selected = $('input[name="name"],input[name="email"]');