So little ______ about China that ho could not find Beijing in the world map.

What is the minimum salary, Sunlife offers to their potential employeesIt offers ______ per month.

A．Language is to be viewed with ranks or grades.
B．Most languages of "backward" groups are complex enough to express ideas.
C．Generally languages are probably developed from simple sounds.
D．All languages seem to possess the system for vocabulary expansion.