Technology Report - How Technology Has, and Has Not, Changed Since 9-11 科技报道 - 911袭击以来启用与尚未启用的新技术 This is the VOA Special English Technology Report. 这里是美国之音慢速英语科技报道。 It has been te...
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Since 用来说明动作起始时间,for用来说明动作延续时间长度。 I have lived here for more than twenty years. I have lived here since I was born.. My aunt has worked in a clinic sinc...