The first one could be "care".
The second could be "rest".
Four letter word(s) meaning/relating to 'concerned':
- Care *- Feel *
Four letter word(s) meaning/relating to 'tranquility':
- Rest - Calm - Still
The answer to the first part is "care," which means to be concerned about someone or something. The answer to the second part is "calm," describing a state of tranquility. Both words reflect important emotional states.
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