string(230) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=blackboard%E7%94%A8%E8%8B%B1%E8%AF%AD%E6%80%8E%E4%B9%88%E5%BF%B5 => Failed to connect to 14.18.117.71 port 38164: Connection refused"
blackboard用英语怎么念
