$1$. I didn't go to school yesterday
`->`yesterday ( dấu hiệu thì QKD )
$2$. He has lived in this city since he was small
`->`HTHT + since + QKD
$3$. They will visit their grandparents this weekend
`->`this weekend ( dấu hiệu thì TLD )
$4$. My school is the biggest in my city
`->`So sánh nhất với tính từ ngắn: S + be + the + adj-est + N