高考英语两道单选题对比~~~~~~~~~求解
1.Hehaswrittenthreebooksoncomputernetworking,_____onebecameabest-sellerandwaspublishedintwelvelanguages.
答案是ofwhich
2.Mr.Greenhastwosons,oneof____workingasabusdrivernow.
答案是them
请问这两道题有什么区别?