4、不过一旦你熟能生巧?小朋友们,你们的逆天时刻就到啦!最后给大家一个经典案列示范,先挑战读一读,后面会教你如何总结。经典案例ThePhonautograph eventually evolvedintothePhonograph. ThomasEdisondiscoveredin1878awaytorecordsoundontosoft.Impressionablematerialsuchastinfoil,leadorwax.However,itwasnotuntil1887thatthisdiscoverywasusedtorecordsoundonaf