Hello teachers
I am nowadays preparing for exam , I read these sentences in some lessons but I really face problems to know what do they really mean . some of them I know what they mean but when I try to translate them I confuse a bit , so please would you explain them in a clear way that help me in translating them smoothly
the sentences are
Robin Cook has resigned from Tony Blair's cabinet as the built-up to war with Iraq gathers pace ( Built-up to war with Iraq gather pace )
The UK , US , Spain have effectively abandoned their efforts to find a diplomatic solution to the stand-off ..( what does abandoned their efforts means as well as what does stand-off means ? )

Thanks in advance