1.Research___allovertheworldintothepossiblecauseofcancerinthepastyears.A.wasmadeB.hadbeenmadeC.hasbeenmakingD.hasbeenmade2.Fibersofhairandwoolarenotcontinuousandmustnormallybespunintothread___wovenintotextil

　　1.Research___allovertheworldintothepossiblecauseofcancer inthepastyears.

　　A.wasmade B.hadbeenmade C.hasbeen making D.hasbeenmade

　　2.Fibersofhairandwoolarenotcontinuousandmustnormallybespunintothread___wovenintotextilefabrics.

　　A.asarethey B.whentobe C.thattheyare D.iftheyaretobe

　　3.Allthetasks____aheadoftime,theydecidedtogoonholidayforaweek.

　　A.hadbeenfulfilled B.havingbeenfulfilled C.werefulfilled D.beenfulfilled

　　4.Hewasashamed___topasstheexam.

　　A.tofail B.tohavefailed C.tobefailed D.tobefailing

　　用括号里给出单词的正确形式填空

　　_____(see)fromthetopofthetower,theprofessorgaveusawarmwelcome.

　　_____(finish)thepainting,hebegantomakeaframeforit.

　　_____(face) withdifficulties,wemusttrytoovercomethem.

　　2题答案是D,

　　还有填空_Seen____(see)from..._Faced___(face)withdifficulties.....我也很费解。

　　为什么___Havingfinished__(finish)thepainting.用Having，而__Faced___(face)withdifficulties用过去分词，