根据所给情景,完成下列对话,每空一词.

A:_____that?
B:that's sam.
A:__Do___You know him?
B:yes,he's my good friend.
A:Why___do___you like him?__He____looks so serious.
B:__Because___he's funny.He can talk like our teacher.
A:__How___is he___like__?
B:He's outgoing and friendly__to___others.
A:But I don't like a boy__with___so long hair.
B:It's not important.I think he's__the___best student
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