One week after her 100th birthday, Maria Soledad Sarabia Lagareta stood in a federal court room in downtown Honolulu and said the oath of allegiance to become a U.S. citizen, nearly 80 years after she moved to the country.

"I feel wonderful," the Mexican-born Lagareta said in Spanish with her son Roland Lagareta, 61, acting as her interpreter.

Dressed in a yellow muumuu and a yellow-ribboned white hat for Wednesday's ceremony, Lagareta said she decided to become an American because she lived here.

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She yearned to vote and otherwise participate in her adopted country, her other son, Bruce Lagareta, 59, added, especially after her relatives started raising money for political candidates and she met a few politicians.

The ceremony culminated a long journey for Lagareta, born on May 25, 1906, in Mazatlan along Mexico's western coast as the second of three daughters. Orphaned when her father died in the 1918 influenza pandemic, Lagareta moved to Los Angeles with her aunt's family when she was 21.

She became a seamstress, got married, had two sons, and was widowed — all by 1962. She moved to Hawaii in 1976, seven years after both sons moved to the islands.

Roland and Bruce Lagareta, who were both born in America, said their mother didn't bring up the idea of becoming a U.S. citizen until about 10 years ago.

The U.S. Citizenship and Immigration Service approved her request on Tuesday, just a few weeks after Roland Lagareta helped her fill out and submit a 12-page application form.

Her sons said carefully maintained records, including her birth certificate and her Mexican passport dating to the 1930s, facilitated the speedy approval.

An expedited application process for elderly Americans also played a part, said her daughter-in-law, Kitty Lagareta, who is the chairwoman of the University of Hawaii Board of Regents.

Animated in her native Spanish, Lagareta told reporters after her naturalization ceremony that her lack of vices — no smoking, no drinking — was her secret to longevity. She said emigrating was her best memory of living in America.

"Her motives to become a citizen are borne from wanting to participate, so I feel she's accomplished what she wants to do," Bruce Lagareta said.

Asked what she wants to do now, Lagareta said, "To live."