When Mr. Green knew his children would go to the lake for a picnic, he warned them _______ the lake.
A.to keep away from B.keeping away from
C.keep away from D.kept away from
There __________ a big tree in front of my house . I could hear many birds sing in it .
A.used to be B.is used to be
C.used to have D.was used to be
I don't know if Jenny _______to my party this weekend. If she _______, I'll be happy.
A.will come; come B.will come; comes
C.come; will come D.comes; will come
I’ll _______ the time of the trains to Chengdu as soon as I get to the railway station.
A.look at B.look for C.look up D.look up to
_______ it’s difficult to make it to the top, I still want to have a try.
A.Because B.As soon as C.Before D.Even though
Great changes _______ in our school during the past few years.
A.have taken place B.took place C.take place D.will take place
