Cause and result: 由于, 因此, 于是, 结果, 既然…就

More ways to say "because" and "so"

You know 因为…所以 from Because, although, if: 因为…所以, 虽然…但是, 如果…就. B1 adds words that each carry a little more meaning.

• 由于天气原因，航班推迟了。Due to the weather, the flight was delayed.
• 他每天练习，因此进步很快。He practises every day, so he's improving fast.
• 我等了半天他也没来，于是我一个人走了。I waited ages and he didn't come, so I left on my own.
• 他没带伞，结果被雨淋湿了。He didn't take an umbrella and ended up soaked.
• 既然你已经决定了，就去做吧。Since you've already decided, go ahead and do it.
• 因为太贵了，所以我没买。It was too expensive, so I didn't buy it.

于是 tells a story

于是 reports an action that followed. It can't introduce advice, a request or the future: for "so (you should)…" use 所以.

结果: how it turned out

结果 is literally "result". As a link word it gives the outcome, often a surprise or a disappointment: 我以为他会来，结果他没来.

既然 … 就

既然 introduces a fact the listener already accepts ("since you're here anyway"). The second half, with 就, says what follows: advice (就别去了), a decision or a question (既然知道，为什么不说？).

因为 gives new information ("because"); 既然 builds on what both of you already know ("seeing that").

Common mistakes

• 既然你累了，所以休息吧。 → 既然你累了，就休息吧。 既然 pairs with 就, not 所以.
• 天要下雨了，于是你带把伞吧。 → 天要下雨了，你带把伞吧。 (or 所以你带把伞吧) 于是 tells what happened, not what to do.
• 因为他病了，因此他没来。 (not wrong, but less natural) → 因为他病了，所以他没来。 or 由于他病了，因此没来。 因为 normally pairs with 所以; 因此 sits better after 由于 or on its own.