从而: thereby, thus
连词 / conjunctions
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
从而 links an action or measure to its logical (usually positive) result: "thereby", "thus", "which in turn". Written register (reports, economics, policy).
It opens the second clause, without repeating the subject, and is followed by a verb (提高、促进、减少、实现…). Versus 因此: 因此 marks a consequence; 从而 stresses the mechanism: "by this means".
Examples
政府降低了税收，从而促进了消费。
Zhèngfǔ jiàngdī le shuìshōu, cóngér cùjìn le xiāofèi.The government cut taxes, thereby boosting consumption.
公司改进了技术，从而大大降低了成本。
Gōngsī gǎijìn le jìshù, cóngér dàdà jiàngdī le chéngběn.The company improved its technology and thus greatly cut costs.
多读书可以开阔眼界，从而更好地理解世界。
Duō dú shū kěyǐ kāikuò yǎnjiè, cóngér gèng hǎo de lǐjiě shìjiè.Reading widens your horizons and so helps you understand the world better.
Common mistakes
✗ 从而他们… → ✓ 从而 + verb directly (no new subject).
✗ 从而 in casual speech: ✗ 我饿了，从而去吃饭 → ✓ 所以/于是。
✗ Mixing up 从而 and 从此 ("from then on", a time starting point).