"when the pressure relief valve is closed,the valve is in a line with the bottom of the wing." the above sentence means "当压力释放活门关闭时,它与大翼底部成一条直线".
A.1
正确答案是A
"when the pressure relief valve is closed,the valve is in a line with the bottom of the wing." the above sentence means "当压力释放活门关闭时,它与大翼底部成一条直线".
A.1
正确答案是A