i think they're oranges.
no,they_18___.they're apples.they're yellow apples
are__19__your apples?
no,they aren't.they are my__20__
17.a.this b.those c.that d.it
18.a.isn't b.is c.are d.aren't.
19.a.it b.you c.they d.we
20a.thechers b.teacher's c.teacher' d.teachers's
參考答案:18 d
19 c
20b
17 b