CONCERN - PRESENT SIMPLE
★ i concern
★ you concern
★ he/she/it concerns
★ we concern
★ you concern
★ they concern
CONCERN - PRESENT CONTINUOUS
★ i am concerning
★ you are concerning
★ he/she/it is concerning
★ we are concerning
★you are concerning
★ they are concerning
CONCERN - PRESENT PERFECT
★ i have concerned
★ you have concerned
★ he/she/it has concerned
★ we have concerned
★ you have concerned
★ they have concerned

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