//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 = $('[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]');