Continue heating until steam _____.
| A．has appeared | B．appear | C．appeared | D．will appear |
阅读下面材料，在空白处填入适当内容（不多于3个单词）或括号内单词的正确形式。
Mr.Joneswokeearlyonemorning.Itwasabeautifulmorning,sowenttothewindowandlooked
out.Hewassurprisedtoseeaneatlydressed,middle-agedprofessor,workedintheuniversitynearhis
house.Hehadgreyhairandthickglasses,andwascarryingumbrella,amorningnewspaperandabag.Mr.Jonesthoughtthathemust
(arrive)bythenighttrainanddecidedtowalktotheuniversityinstead
of (take)ataxi.
Mr.Joneshadabigtreeinhisgarden,andthechildrenhadtiedalongropetooneofitsbranches,sothat
theycouldswingonit.
Mr.Joneswassurprisedtoseetheprofessorstopandlook (care)upanddowntheroad.
hesawthattherewasnobodyinsight,hesteppedintothegarden(therewasnofence), puthisumbrella,
newspaper,bagandhatneatlyonthegrassandtookholdoftherope.Hepulledithard (see)whetheritwasstrongenoughtotakehisweight,then
(run)asfastashecouldandswungintotheairontheend
oftherope.'
Atlasttheprofessorstoppedandcontinuedonhiswaytheuniversity,lookingasquietandcorrect
asonewouldexpectaprofessortobe.
—Shall I open the window to let in some fresh air?
—______ It’s really hot in here.
| A．What a pity. | B．Sure, go ahead. |
| C．Why not? | D．It’s up to you. |
Though he didn’t perform well in the French Open, he is still ______ the top ten in the world.
| A．among | B．of | C．in | D．above |
—Where’s my driving license? Maybe I left it at home.
—My Goodness! I ______ you would always take it along.
| A．was to think | B．thought |
| C．have thought | D．have been thinking |
Though the training cost a lot of time and effort, I do think it ______.
| A．valuable | B．significant | C．worthwhile | D．vital |