`49.` Long hasn't had his hair cut for over 6 months.
Giải thích: It's + [quãng thời gian] + since + S + last + V-ed = S + have/has + not + Vpp + for [quãng thời gian].
`50.` Jane eats very little because she doesn't want to put on weight.
Giải thích: want to V: muốn làm gì.
@ `Ly`
