English grammar error-spotting (reciprocal preposition: ‘‘among themselves’’, not ‘‘between themselves’’ for 3+): ‘‘All the four sons / of the old man / quarrelled between themselves. / No error.’’ Mark the erroneous part.

Concept / ApproachUse ‘‘between’’ for two; ‘‘among’’ for three or more. With four sons, the reciprocal phrase must be ‘‘among themselves’’.

CorrectionsPrimary: ‘‘… quarrelled among themselves.’’Stylistic: ‘‘All four sons …’’ is crisper than ‘‘All the four sons …’’

Final Answerquarrelled between themselves.