... so I opened the window

Grammar notes

So Shows the Result (Conjunction: So)

Use so for a result or consequence.

One thing happens, and so introduces what came next.

It is the natural partner of cause-and-effect stories.

• Example: I was hungry, so I made a sandwich.
• Example: It rained, so we stayed inside.

Quick Rule

• first idea + so + result
• use it when the second part follows from the first

If because gives the reason, so gives the result.