Please do me a favor—________ my friend Mr.Smith to Youth Theater at 7：30 tonight.
A．to invite B．inviting
C．invite D．invited
Nowadays people sometimes separate their waste to make it easier for it ________.
A．reusing B．reused
C．reuses D．to be reused
At the age of 29，Dave was a worker，________ in a small apartment near Boston and ________ what to do about his future.
A．living；wondering B．lived；wondering
C．lived；wondered D．living；wondered
When he ________ the door，he found his keys were nowhere.
A．would open B．opened
C．had opened D．was to open
In April,2009，President Hu inspected the warships in Qingdao，________ the 60th anniversary of the founding of the PLA Navy.
A．marking B．marked
C．having marked D．being marked
________ not to miss the flight at 15：20，the manager set out for the airport in a hurry.
A．Reminding B．Reminded
C．To remind D．Having reminded
