Sarah是班长,老师走进教室准备上课,她应该这样说:A. Sit down.B. Good morning.C. Stand up.
I must ______ the traffic lights. A.look after B. pay attention to C. look for
There is a picture _____ a bike. A.in B. of C. at
In the USA, people on bikes must ____ a helmet. A. on B. put on C. wear
There are always three lights: red, yellow and ______. A. green B. blue C. orange
How do you get to the USA ________ China? A. for B. to C. from