bus has two tiers
this is a tourist bus
buses on the grass
a double decker bus
the buses are parked
Three yellow and green buses 
Green bus with yellow trim
Buses parked on grass
Bus on the grass
two double decker buses
a green and yellow bus
a green and tan bus
three similar buses but different
Double decker bus is parked
a green and yellow double decker bus
a green double decker bus
the green double decker bus is in the middle
the bus is parked in a field
the green bus is parked in a field
there are three buses 
the buses are all green 
this bus is green and yellow 
this is a green bus with white accents 
this is a double decker bus 
there are two double decker buses 
the buses are parked on grass 
a double decker bus parked in the grass