who was that boy you ? You were with him this morning -> who was

Who was that boy you ? You were with him this morning 

=> Who was that boy with whom you were this morning

Nghĩa: Chàng trai mà bạn ở cùng sáng nay là ai vậy ?

 That boy là người nên dùng dùng đại tù quan hệ whom và đặt giới từ with ở trước nó 

       "That boy" tương đương "with him"

    Chúc bn hc tốt !

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