White phosphorus, a substance__________ in matches, is so flammable that it burst into flame upon contact with the air.

A. have completed                       

B. had completed

C. will have completed                    

D. would have completed

A. truth.               

B. facts                

C. things               

D. information

A. has tried / was given                             

B. have tried / were given

C. has tried / were given                             

D. have tried / was given

A. I will, first thing in the morning.            

B. I can get a paper for you.

C. I'm not sure.                                           

D. I'm with you there.

A. won’t look                

B. wouldn’t look           

C. wouldn’t have looked         

D. looked

A. just                            

B. nutritious                  

C. quick                

D. convenient

A. Yes, I am.                  

B. I'll never change my mind. 

C. Have I?

D. Oh, sorry,I can't.