Six

1.press pressure suppress

impress impressive impression

express expressive expression

depress depressed depressive depression

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The Great Depression

2.memo memory memorize memorial  remember commemorate

3.postpone

oppose opposite opponent

compose composite component composition

dispose disposable

propose deposit

4.struct

construct constructive construction

destruct destructive destruction

instruct instructive instruction instructor

obstruct obstructive obstruction

5.perplex perplexed confuse confused

complex complicated complication

imply implicative implication

duplicate

A comply conform consist with B