Expression introID is undefined on line 34, column 51 in tpl/2015/d/www.deflecto.cn/en/introduce.html.
The problematic instruction:
----------
==> ${introID} [on line 34, column 49 in tpl/2015/d/www.deflecto.cn/en/introduce.html]
 in user-directive mytag.viewIntroduce [on line 34, column 1 in tpl/2015/d/www.deflecto.cn/en/introduce.html]
----------

Java backtrace for programmers:
----------
freemarker.core.InvalidReferenceException: Expression introID is undefined on line 34, column 51 in tpl/2015/d/www.deflecto.cn/en/introduce.html.
	at freemarker.core.TemplateObject.assertNonNull(TemplateObject.java:124)
	at freemarker.core.Expression.getStringValue(Expression.java:118)
	at freemarker.core.Expression.getStringValue(Expression.java:93)
	at freemarker.core.DollarVariable.accept(DollarVariable.java:76)
	at freemarker.core.Environment.visit(Environment.java:245)
	at freemarker.core.MixedContent.accept(MixedContent.java:92)
	at freemarker.core.Environment.visit(Environment.java:245)
	at freemarker.core.Environment.renderElementToString(Environment.java:1510)
	at freemarker.core.StringLiteral.getStringValue(StringLiteral.java:95)
	at freemarker.core.StringLiteral._getAsTemplateModel(StringLiteral.java:80)
	at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
	at freemarker.core.UnifiedCall.accept(UnifiedCall.java:110)
	at freemarker.core.Environment.visit(Environment.java:245)
	at freemarker.core.MixedContent.accept(MixedContent.java:92)
	at freemarker.core.Environment.visit(Environment.java:245)
	at freemarker.core.Environment.process(Environment.java:225)
	at freemarker.template.Template.process(Template.java:118)
	at freemarker.ext.servlet.FreemarkerServlet.process(FreemarkerServlet.java:310)
	at freemarker.ext.servlet.FreemarkerServlet.doGet(FreemarkerServlet.java:245)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:624)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.tuckey.web.filters.urlrewrite.UrlRewriteFilter.doFilter(UrlRewriteFilter.java:738)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at shield.front.action.filter.NotAllowedToTunFilesFilter.doFilter(NotAllowedToTunFilesFilter.java:126)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at shield.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:69)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at shield.front.action.filter.InvalidXSSFilter.doFilter(InvalidXSSFilter.java:68)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:442)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1082)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:623)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1756)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1715)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:662)