Why many adolescents have trouble communicating with their parents lies in _______we call “generation gap .”
| A．what | B．that | C．which | D．how |
93. The diligent student refused the help of others and insisted on working out the difficult maths problem _____.
| A．on his own | B．in his own | C．of his own | D．for his own |
92. It was good ______ you to invite me to join in the party.
| A．for | B．in | C．to | D．Of |
91. They are going to erect(树立) a monument _____ memory of the men who offered their lives in defense of their country.
| A．on | B．for | C．to | D．in |
90. --- Who is that gentleman who talked to you just now?
--- He is my uncle _____ marriage.
| A．at | B．to | C．by | D．With |
89. Was this piece of earthenware(陶器) made machine or _____ hand?
| A．by; by | B．with; by | C．with; with | D．by; with |