---Is Lucy ______ her homework?
--- No , she ________ .
A．do; doesn’t B．does; isn’t C．doing; is D．doing; isn’t
--- Shenzhen is a beautiful city.
--- Yes. You can see a lot of flowers and trees on ________ of the streets .
A．both sides B．all sides C．both side D．all side
-- What can trees do _________ us ?
--- They can _________ harmful gases and produce oxygen .
A．helping , take in B．to help , take in C．helping , take out D．to help , take care
--- Next week , we will go to visit your school .
--- You are welcome _________ our school and you can go _________ to have a look .
A．visit , somewhere B．to visit , anywhere C．to visit , nowhere D．visiting , anywhere
--- Tom is one of _________ students in my class .
--- Yes . He usually prefers _________ at home to playing outside .
A．the most hard-working , studying B．more hard-working , to study
C．the most hard-working , to study D．more hard-working , studying
--- We don’t allow _________ in the library .
--- So we had better _________ outside .
A．smoking , smoking B．to smoke , smoking
C．to smoke , to smoke D．smoking , smoke
