21. --- Could I ask you a rather personal question?
--- Sure, ____.
A. pardon me B. go ahead C. good idea D. forget it
22. It’s not ___ good idea to drive for four hours without ___ break.
A. a ; a B. the ; a C. the ; the D. a ; the
23.—I have got a headache.
—No wonder. You in front of that computer too long.
A. work B. are working C. have been working D. worked
