The answer is simple, you need to have a good brain...something you appear to lack...along with money for a membership 
forced mate indication
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I don't have a premium so I don't know if there is the possibility but I thought it would be nice to have an option when playing against computer to toggle notifying when computer found forced mate possible (or forced mate in # for easy) so you can train faster spotting of the mate in regular plays not just puzzles that don't have any "backstory"