________ many times, he finally understood it．
A．Told B．Telling C．Having told D．Having been told
19．
He told us whether _________ a picnic was still under discussion
A．to have B．having C．have D．had
18．
David threatened_______ his neighbour to the police if the damages were not paid．
A．to be reported B．reporting C．to report D．having reported
17．
Ladies and gentlemen, please remain __________ until the plane has come to a complete stop．
A．seated B．seating C．to seat D．seat
16．
Bill suggested _____ a meeting on what to do for the Shanghai Expo during the vacation．
A．having held B．to hold C．holding D．hold
15．
With the government’s aid, those _____ by the earthquake have moved to the new settlements．
A．affect B．affecting C．affected D．were affected
14．
