Use "both" or "the two"

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!

 boys looked at the girl in bewilderment.
None of them knew her but they were
She looked at
 of them, one after the other.
 blushed as she was staring at them.
She turned roundn and they
 watched her go.