whEn prACtiCingtAsk-BAsED lAnguAgE tEAChing, thE ClAss BEArs thE Following FEAturEs ExCEpt________.
A．lAnguAgE istExt-BAsED AnD DisCoursE-BAsED
B．lExiCAl units ArECEntrAl in lAnguAgE usE AnD lAnguAgE lEArning
C．ConvErsAtion isthE CEntrAl FoCus oF lAnguAgE AnD kEystonE oF lAnguAgE ACquisition
D．ACtivitiEsproviDE Both thE input AnD output proCEssing nECEssAry oF lAnguAgE ACquisition