please, suit, be acceptable
If someone is implacable, they very stubbornly react to situations or the opinions of others because of strong feelings that make them unwilling to change their mind.
Complacent persons are too confident and relaxed because they think that they can deal with a situation easily; however, in many circumstances, this is not the case.
A placid scene or person is calm, quiet, and undisturbed—and generally tends to remain so.
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