A five-year-old child knows over six thousand words he or she has also learned more than one thousand rules of grammar.

A、A five-year-old child knows over six thousand words, he or she has also learned more than one thousand rules of grammar.

B、A five-year-old child knows over six thousand words. He or she, has also learned more than one thousand rules of grammar.

C、A five-year-old child knows over six thousand words. He, or she has also learned more than one thousand rules of grammar.

D、A five-year-old child knows over six thousand words, and he or she has also learned more than one thousand rules of grammar.

正确答案：A five-year-old child knows over six thousand words, and he or she has also learned more than one thousand rules of grammar.