Would you like to go ________?
---Is Lucy ______ her homework?--- No , she ________ .
--- Shenzhen is a beautiful city. --- Yes. You can see a lot of flowers and trees on ________ of the streets .
-- What can trees do _________ us ?--- They can _________ harmful gases and produce oxygen .
--- Next week , we will go to visit your school .--- You are welcome _________ our school and you can go _________ to have a look .
--- Tom is one of _________ students in my class . --- Yes . He usually prefers _________ at home to playing outside .