Sentence:  'Patience,' said Slartibartfast again. 'Great things are <WSD>afoot</WSD>.'/ 'That's what you said last time we met,' said Arthur./ 'They were,' said Slartibartfast./ 'Yes, that's true,' admitted Arthur. 
Meaning of the word marked with <WSD> tags:  In motion; in action; astir; stirring; in progress.