1)Because Nga was sick, she didn't go to school yesterday.

>Nga was

2)I don't know your phone number.

>I wish

3)I bought that school bag last year

>That schoolbag

1) Nga was sick so she didn't go to school yesterday

2)I wish knew your phone number

3)That schoolbag was bought last year

`1`. Nga was sick so she didn't go to school yesterday.

`-` S + V + so + S + V: ... vậy nên ...

`2`. I wish I knew your phone number.

`-` Câu ước ở hiện tại: S + wish(es) + S + V-ed/c2

`3`. That schoolbag was bought by me last year.

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