The boy was so careless that the glass fell from his hand and it ______ on the floor.
Children need friends________their own age to play with.
________we will do is to leave a note to tell Mum we will be back late.
Both________and________laughing do harm to your health.
The great artist Xu Beihong is famous for________to horses in his arts.
I was ashamed________wasting many hours when I should have been studying.