`-` BĐ :

`+` HTĐ : S + is / am / are + VpII ( by O )

`+` QKĐ : S + was / were + VpII ( by O )

`+` HTTD : S + is / am / are + being + VpII ( by O )

`+` HTHT : S + have / has + been + VpII ( by O )

`+` ĐTKT : S + ĐTKT + be + VpII ( by O )

`18`.Hats and coats were left here

`19`.The meeting can't be held in that room

`20`.The bill has to be paid

`21`.For the time being , that group is being taught by Alice

`22`.The report has been finished

`23`.Five suspects have been arrested by the police

`24`.The little boy was bitten by the mad dog

`25`.Our exercises are corrected by the teacher

`26`.The accident was seen by Mr.Smith

`27`.A dancing class was started last week

`28`.The package should be insured

`29`.The bill may be paid for us

`30`.The plants ought to be watered once a week

`31`.The mail is being delivered by the mailman now

`32`.My briefcase has been taken

`\text{# TF}`