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Core Words Familarize yourself with the 'core words'.
Compounds Expand your vocabulary by studying more complex words built by the 'core words'.
Etymology Explore the origin of the 'core words'.

{n}	frown	(facial expression)	finsterer Blick, Stirnrunzeln {n}
{v}	frown	finster dreinblicken , missbilligen
{v}	frown	(to have a frown on one's face)	die Stirn runzeln, runzeln