Can anyone think of a word which will go in front of 'umbrella' to make a two word phrase? The same word has also to go in front of 'beat' 'dancing' 'memory' and chamber to make four more two word phrases.
DRUM.
It might sound improbable, but if you do a Google search you will find that two-word combinations exist for all of them, using 'drum'. For example, putting "drum chamber" into the search slot will reveal that there is something called a 'drum-chamber coil mattress'. All the others work out, too, though I'm still far from sure what a 'drum umbrella' is! (Click http://www.educ8r.net/shopping/B0000AV519.htm
and scroll down to No 11 for the reference.)