They can't work/function on their own... and they're short. Hope this helps!
Helps organize and keeps things in order
Explanation:
She will be singing a song.
<em>Past </em><em>perfect</em><em>:</em><em>-</em>
<em>Structure</em><em>=</em><em> </em><em>subject+</em><em>had+</em><em>v³</em><em>+</em><em>object</em><em>.</em>
Answer:- She had sung a song.
Where,
subject= she
V³= sung
object= a song
