During the week I train with effort to try and put Leonardo in difficulty: I'm here to play my CARDS and help my team-mates.

这一周，自己在训练中很刻苦，这让莱昂纳多选择时犯了难：我来到这里，就是打出自己的水平，帮助队友的。

youdao

It is very complex to calculate the aerodynamic drag of high-speed train running in railway tunnel with multi -shafts. And the difficulty is to calculate the velocity of piston wind.

在高速列车空气阻力计算中，多竖井隧道的列车空气阻力计算比较复杂，其难点在于多竖井的活塞风计算。

youdao