Original sentence: Although she at first finds alien time traveller the Doctor terrifying, their initial encounter leaves her unsatisfied, and she decides to travel alongside him when the next opportunity arises.In a contrast to the Tenth Doctor's prior companions, who both harboured romantic feelings for him, Donna and the Doctor shared a strictly friendly relationship, and she does not feel the need to prove herself to travel with the Doctor; the Doctor refers to her as his "best mate"
Edited sentence: Although she at first finds alien time traveler the Doctor terrifying, their initial encounter leaves her unsatisfied, and she decides to travel alongside him when the next opportunity arises.In a contrast to the Tenth Doctor's prior companions, who both harbored romantic feelings for him, Donna and the Doctor shared a strictly friendly relationship, and she does not feel the need to prove herself to travel with the Doctor; the Doctor refers to her as his "best mate".Sassy, independent, and utterly human, Donna makes a wonderful companion and was a great contribution to the show