early sign早期标志earlyadv.早adj.早Early differentiation antigens早期分化抗原early in the twentieth century20世纪初期early anti-cracking property早期抗裂性Early Spring Greeting from NYC纽约的早春问候early iron-deficiency anemia铁缺乏症早期Early maturity tobacco variety早熟品种early warning detection system预警探测系统Early Precambrian stratigraphy进展early literacy teaching method早期读写教学法Early necrosis of femoral head早期股骨头坏死