—— Why? Tom, your shirt is so dirty!
—— Mum, I ＿＿＿＿＿ my storeroom downstairs。
| A．cleaned | B．have worked |
| C．was cleaning | D．have been cleaning |
An accident happened atcrossroads a few metres away from bank.
| A．a…a | B．/ … a | C．/ … the | D．the…/ |
（年山东日照市高三校际联合检测）l.We can never expect____bluer sky unless we create_____less polluted world．
| A．a；a | B．a；the | C．the；a | D．the；the |
—I knocked over my coffee cup. It went right over _________ keyboard.
— You shouldn't put drinks near _________ computer.
| A．the;不填 | B．the;a | C．a;不填 | D．a;a |
（年安徽省合肥市高三第三次教学质量检测）21. Gottlieb Daimler, ______ German engineer, is normally believed to have invented ______ car.
| A．a; 不填 | B．a; the | C．the; a | D．不填; a |
_____ I cannot understand is _____ she wants to resign her present job.
| A．What; why | B．Which; how | C．That; why | D．What; which |