alegrarse

v. be glad, rejoice; liven up, brighten

(v.) = feel + elated, brighten
Ex: Jeanne Leforte felt tired but elated when the session adjourned. Ex: 'And of course,' said the director, brightening as his idea gave birth to another one in her mind, 'it will be interesting to know how efficient electronic systems are at catching thieves'.

= jazz up.
Ex: After jazzing up her appearance with a new blonde hairdo, she turns up in his office and talks him into taking her out for a meal.
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* alegrarse = feel + elated, brighten.
* alegrarse de = be glad (to), rejoice in.