请选择ABCD2W1d7?(I The farmers ________ 5 000 new words by the end of last year.9d;E+j*V)R7r.U
A. have learnt9d;E+j*V)R7r.U
B. learnt9d;E+j*V)R7r.U
C. would learn9d;E+j*V)R7r.U
D. had learnt9d;E+j*V)R7r.U