20、

1．What lesson do they have at 1：45 p．m．on Wednesday?

A．Physics．            B．Chemistry．         C．History．                D．Math．

2．Do they have lessons at 10：30 a．m．on Tuesday?

A．Yes，they have．                                    B．No，they don't．

C．We can't know from the timetable．             D．None of the above（以上都不是）．

3．On Friday，a physics lesson begins at _________．

A．9：10 a．m．    B．10：30 a．m．       C．1：45 p．m．        D．3：00 p．m．

4．How many lessons do they have in a week?

A．10．                   B．11．                    C．12．                      D．13．

5．How many kinds of lessons do they have in a week?

A．3．                        B．4．                     C．5．                        D．6．