一、定语从句用who或that做引导词,在从句中做主语.
Thepersonwholostthelibrarybookmustpayforit.
Theboywhoiswearingtheblackjacketisveryclever.
二、定语从句用who,whom或that做引导词,在从句中做宾语.因为是做宾语,所以这些引导词可以省略.
Mr.Leewho/whom/thatyouwanttoseehascome.
Thisisthegirlwhom/that/whoheworkedwithintheoffice.
三、定语从句用whose做引导词,在从句中作定语表示“某些人的…”.
TheboywhoseparentsweredeadiscalledLiLei.
Mr.WangisthepolicemanwhosehousecaughtfirelastSunday.