16, are -> is
17, D. walking
18, D – acquaintance
19, This is the man whom I sold my bike to.
20, The computer which I bought last week isn’t powerful enough.
21, I know the woman who makes locks and keys.
22, This is the school where I used to go.
23, A – leisure
24, C – volunteers
25, B – forbid (v, ngăn cấm)
26, B – I spoke to
27, B – education
28, A – from
29, who -> that
30, D - Although
