【单选题】— _____ have you been learning English? — I have been learning English for six years. [ ]
【单选题】下列哪个软件可支持对网络硬仿真测试数据进行批量模型校正?
【单选题】—Oh, you have a headache and a cough.______ have you been like this? —Two days. [ ]
【单选题】—How many times have you been to China? —In fact, it is the first time I __________ here.
【单选题】______ have you been in this country?