Subject + 选定 + Object
选定 (xuǎndìng) means "to select" or "to designate," with the complement 定 indicating that the choice is final and settled. It implies a definitive selection, as in 选定的人 (the chosen person).
经过反复比较,她终于选定了一套房子。
jīngguò fǎnfù bǐjiào, tā zhōngyú xuǎndìng le yī tào fángzi.
After repeated comparisons, she finally chose an apartment.
公司已经选定了新的合作伙伴。
gōngsī yǐjīng xuǎndìng le xīn de hézuò huǒbàn.
The company has already selected a new partner.
你选定了目标就要坚持下去。
nǐ xuǎndìng le mùbiāo jiù yào jiānchí xiàqù.
Once you've chosen your goal, you must persevere.