I know a British lady who was on her 1st trip to the USA. On her last day she had to get up early to be at the airport in time. She went to the male reception desk clerk and said '' I have an early flight, so can you come and Knock me up at 6am?'' Poor girl had no idea what ''Knock up'' meant in American slang.
She could not understand why the guy looked bemused .
Just in case people on here do not understand, in the USA / Canada to 'knock someone up' means to make them pregnant ! It is a rather rude way of putting it, rather like 'put me up the duff' in the UK.