There____six countries in SCO(上合组织) at first, but now the number has increased to eight.( )
A.isB.areC.wereD.will be
It was not long John returned with bags of food in his hands.( )
until
before
when
﹣What is this?
﹣It's pencil.( )
the
an
a
Help yourself to some_________,Jim.( )
potato
fish
egg
Li Ying cleans her room the weekend.( )
at
for
in
﹣ you swim?
﹣Yes, I can.( )
Must
May
Can