6. The teacher suggests that we ……………. harder on pronunciation. A. worked B. working C. should work D. to work 7. The train couldn’t run ……………. snow. A. because B. because of C. since D. for 8. What songs do people often sing ……………. Christmas? A. at B. on C. in D. of 9. You should get a ……………. check the pipes in your bathroom. A .electrician B. carpenter C. mechanic D. plumber 10. She is very kind. She’s always ……………. towards her employees. A. distinguished B. proud C. considerate D. happy