When you are in England, you must be very careful in the streets _    _ the traffic drives on the left.          you cross a street, you must look to the right first _      then the left.
In the morning and in the evening when people go to or come back from work, the streets are very      _. Traffic is the most dangerous then.
When you go by bus in England, you have to be _     _, too. Always remember the traffic moves on the      _. So you must be careful. Have a look first, _    _you will go the wrong way.
In many English cities, there are big buses          two floors. You can sit on the         floor. From there you can see the city very well. It’s quite         .

A．if B．because C．when D．since

A．Before B．After C．As soon as D．When

A．or B．but C．and D．so

A．busy B．free C．big D．beautiful

A．careless B．careful C．excellent D．strict

A．right B．left C．right and left D．right or left

A．and B．so C．or D．but

A．in B．with C．for D．on

A．second B．first C．third D．ground

A．boring B．interesting C．expensive D．safe