21. My grandfather accidentally ?____? fire to the house.?
A.putB. tookC.setD. got?
22. We enjoyed the holiday ?____? the expense.?
A.exceptB. besides?
C. in addition toD. except for?
23. If you want children to work hard you must ?____? their interests instead of their sense of duty.?
A. appeal toB. look intoC. give rise toD. go in for?
24. Basically a robot is a machine which moves, manipulates, joins or processes ?____? in the same way as human hand or arm.?
A. characters B. components?
C.catalogues D. collections?
25. Of course, talking about something which affects them personally is ?____?motivating for students.?
A. chieflyB. correctlyC. currentlyD. eminently