For thousand of years, man has used rocks as main materials for

                                        A                    B

building houses, made fences, pavements or even roofs for houses .

                          C                                                  D

A. despite                            

B. instead                             

C. therefore                          

D. however

A. They are environmentally responsible constructions with gardens

B. They are gaining in popularity in different parts of the world

C. They have only been built in technologically developed countries

D. They are more economical and produce no pollution

A. Wearing helmets is never taken into consideration when driving.

B. Helmets are an optional part of you when you drive.

C. Helmets must be worn at all times when driving.

D. Helmets must be taken around with you when you drive.

A. There is no doubt about it!                        

B. Yes, it's an absorb idea.

C. Well, that's very surprising.                       

D. Of course not, you bet!

A. exploit                     

B. seize                         

C. make use                  

D. get

A. imaginary                

B. isolated                    

C. imaginative              

D. real