按要求改写句子。(20分)
(1)Students enjoy themselves in summer.(改为同义句)
Students________________ ________ ________ in summer.
(2)He is planting rice. (改为一般疑问句)
________he________rice?
(3)Is she making a sandcastle? (作肯定回答)
________,she________.
(4)She is looking for the shells.(改为否定句)
She________ ________for the shells.