Several hypotheses for global warming have been suggested by the scientists

A. No sooner had he started computer programming than he left school

B. Hardly had he started computer programming when he left school

C. No sooner had he left school than he started computer programming

D. After he left school, he had started computer programming

A. You mustn’t have done all this work

B. You couldn’t have done all this work. 

B. You couldn’t have done all this work. 

D. You needn’t have done all this work

A. The police asked what were you doing last night, Mr John

B. The police asked Mr John what he had been doing the night before

C. The police asked Mr John what he had been done the night beforev

D. The police asked Mr John what had he been done the night before

A. the 

C. X 

C. X 

D. an 

A. instruct 

B. instructional 

C. instruction 

D. instructive 

A. not seeing 

B. not to seen 

C. not see 

D. not to see 

A. make my skin march 

B. make my skin turn 

C. make my skin crawl 

D. make my skin walk