。
She took her own life yesterday.
Literal
She [topic-は] yesterday committed-suicide.
自殺する is the standard Sino-Japanese verb for suicide, built from 自 ('self') + 殺 ('kill'). The compactness of Sino-Japanese morphology compresses what English needs three or four words to express. In Japan, 自殺 is a sensitive topic woven into much of postwar social discourse — sustained public-health campaigns, the famously high rates among older men and overworked salarymen, and historical resonances from concepts like 武士の自決 (samurai ritual self-killing). Reporting this kind of news typically uses neutral verbs like this one rather than gentler euphemisms.