grave fault的意思|示意

XML happily permits a number of errors that, although not sufficiently grave to cause a software fault, nevertheless impede smooth reading.

XML允许许多问题存在，这些问题尽管不足以导致软件故障，但会影响流畅的阅读。

Therefore, developing new style and high performance fault recording and analysis device has grave real and economic purpose.

因此，研制开发一种新型的高性能故障录波器具有重大的现实和经济意义。

They have committed a grave fault?

他们犯了很大的错吗？