由于 + Cause Clause,所以/因此 + Result Clause
由于 (yóuyú) functions as a conjunction meaning "due to the fact that" and introduces a causal clause. It can be paired with 所以 or 因此 in the result clause to form a complete cause-and-effect sentence. This usage is characteristic of formal or written Chinese.
由于他表现优秀,所以被提升为主管。
yóuyú tā biǎoxiàn yōuxiù, suǒyǐ bèi tíshēng wéi zhǔguǎn.
Because of his outstanding performance, he was promoted to supervisor.
由于市场需求增加,因此公司决定扩大生产。
yóuyú shìchǎng xūqiú zēngjiā, yīncǐ gōngsī juédìng kuòdà shēngchǎn.
Due to increased market demand, the company decided to expand production.
由于准备充分,所以考试考得很好。
yóuyú zhǔnbèi chōngfèn, suǒyǐ kǎoshì kǎo de hěn hǎo.
Because of thorough preparation, the exam went very well.