We should learn from past mistakes so as to avoid __________ into the same old trap (困境) again.
| A．to fall | B．falling |
| C．having fallen | D．being fallen |
Theboysittingbythewindowistheonlyoneofthestudentswho _______fromthecountrysideinourschool.
| A．are | B．is | C．were | D．was |
Thestudentsinourschooleach_________anEnglishdictionary.
| A．have | B．has | C．had | D．arehaving |
Thepairofshoes__________wornout.
| A．was | B．were | C．havebeen | D．hadbeen |
Aprofessorandawriter_________presentatthemeeting.
| A．was | B．is | C．were | D．hadbeen |
Hisfamily________musiclovers.
| A．allare | B．areall | C．is | D．arebeing |