distingguish between liquidated damages and penalties
the words used to describe the sum are evidence of what the parties intended but are not conclusive
the sum should be treated as a penalty, if grossly disproportionate to the greatest damage likely to result from the breach
where the breach consists of a failure to pay money, the prescribed sum is a penalty if it exceeds the sum payable
where one sum is payable in the event of the commission of any of a number of different breaches ,some of which are trifling and some of which are more serious,it is probably a penalty
even if accurate pre-estimation is almost impossible, this does not prevent a sum from being treated as liquidated damages, as long as it represents a genuine attempt to make a reasonably accurate assessment
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