He is often heard _____ in the next room.A.singing B.sang C.to singing D.to sing 说清楚点
问题描述:
He is often heard _____ in the next room.
A.singing B.sang C.to singing D.to sing
说清楚点
答
He is often heard _____ in the next room.
A.singing B.sang C.to singing D.to sing
说清楚点