Once education is made free many children who have dropped out of school . A. will come ba

问题补充：

Once education is made free，many children who have dropped out of school .

A. will come back

B. came back

C. have come back

D. had come back

答案：

(答案→)A. will come back

B. came back

C. have come back

D. had come back

解析：可联系答.案.网客服索取。