Therefore, it is urgent to carry out research on reconstruction and extension of freeway.

因此，开展高速公路改扩建关键技术的研究是形势所迫。

youdao

Therefore, it is urgent to carry out research on reconstruction and extension of freeway.

因此，开展高速公路改扩建关键技术的研究是形势所迫。

youdao