下列物质中属于碱的是( )
A.食用碱B.烧碱C.纯碱D.生石灰
When we heard the good news, we couldn't help . We were so excited.( )
A.jumpB.to jumpC.jumpingD.jumped
Cars, buses and bikes stop when traffic lights change to red.( )
A.mayB.needC.canD.must
These machines cut grass.( )
A.are used to.B.use to
C.are used forD.use for
Do you know the boy is drawing a picture over there?( )
A.whomB.whatC.whoseD.who
﹣ It's hot today, isn't it?
﹣Yes,it is.Why not your jacket?( )
A.take careB.take offC.take placeD.take after