John and Mary’s room on fire. Many help them put out the fire.
A. are; passer-bys
B. is; passers-by
C. is; passer-bys
D. are; passers-by
网友回答
A. are; passer-bys
(答案→)B. is; passers-by
C. is; passer-bys
D. are; passers-by
解析：“约翰和玛丽的房子着火了，很多路人帮忙扑灭了火。”第一空主语是room 所以填is，passer-by的复数是passers-by，答案B。