“He started studying english four years ago”
Viết lại thành “He has been studying english for four years” hay là “He has studied english for four year” thì đúng
“He started studying english four years ago”
Viết lại thành “He has been studying english for four years” hay là “He has studied english for four year” thì đúng
He has been studying english for four years là đúng
nếu câu sau là He has studied english for four years thì cũng được coi là đúng