Complete the following statements with proper words or expressions according to the course book.The world has about 3000（some put it 5000） languages, which can be grouped into roughly 300 language families on the basis of similarities in their bas
Complete the following statements with proper words or expressions according to the course book.The world has about 3000（some put it 5000） languages, which can be grouped into roughly 300 language families on the basis of similarities in their basic word stock and ( ).
