Do not go into the engine test area without approval.未经批准，不得进入发动机试验区。
A.It is forbidden to go into the engine test area with approval. B.Entering the engine test area must not be approved. C.Approval is a must when entering the engine test area正确答案C
Do not go into the engine test area without approval.未经批准，不得进入发动机试验区。
A.It is forbidden to go into the engine test area with approval. B.Entering the engine test area must not be approved. C.Approval is a must when entering the engine test area正确答案C
