等离子切割，由于融口上面大，下面小，切口断面总有一定斜度，不可能象火焰切割一样垂直，这是一世界性难题。

Plasma cutting, due to melt, the small mouth above, there is always a downward section incision, don't like probably as vertical flame cutting, this is a worldwide problem.

youdao

对于许多年龄象你们这么大的以色列孩子来说，这是他们一生中最兴奋的一夜。

For many Hebrew children about your age, it was the most exciting night of their lives!

youdao