When hitting the higher notes in the chorus ("Oh, can't you see..."), try to keep your larynx lowered to create a solid, dark sound rather than a thin "choir" tone. Guitar Chords (Standard for Female Key)
Several high-quality karaoke versions are specifically tailored for female ranges: every_breath_you_take_sting_acoustic_karaokefem...
To make your "piece" stand out, consider these stylistic and technical approaches: When hitting the higher notes in the chorus