A.盤 B.帶 C.漸進(jìn) D.瞬時(shí)
A.開門時(shí)速度是先快后慢再慢,而關(guān)門時(shí)先快后慢再慢 B.開門時(shí)速度是先慢后快再快,而關(guān)門時(shí)先快后慢再慢 C.開門時(shí)速度是先慢后快再慢,而關(guān)門時(shí)先慢后快再慢 D.開門時(shí)速度是先慢后快再慢,而關(guān)門時(shí)先快后慢再慢