______ hearing the news of the success, he opened his mouth wide, and then had a big smile on his face.

He had to pause from time to time to wipe the sweat from his forehead, because the airconditioningsystem ________. [ ]

He was so deep in thought，thinking of the problem ________ he knocked into the tree without noticing it

Parents should actively urge their children to______the opportunity to join sports teams.

In which part of the play is it　　　　Lily will play a role?