 When asked to brush "to the best of their abilities  " young adults brushed longer, but did not cover any additional parts of their mouths.
<fluency>  When asked to brush "to the best of their abilities  " young adults brushed longer, but did not cover any additional parts of their mouths.
 When asked to brush "to the best of their abilities , " young adults brushed longer, but did not cover any additional parts of their mouths.