【单选题】— _____ have you been learning English? — I have been learning English for six years. [ ]
【单选题】—How many times have you been to China? —In fact, it is the first time I __________ here.
【简答题】一项时间跨度为半个世纪的专项调查研究得出肯定结论:饮用常规量的咖啡对人的心脏无害。因此,咖啡饮用者完全可以放心的享用,只要不过量。 以下哪项最为恰当的指出了上述论证的漏洞?( )
【单选题】______ have you been in this country?
【单选题】曹丕在哪一篇文章中第一次提出了“建安七子”的概念?