Gör dig färdig för att gå till sängs.

[davidculley]

English Translation

Get ready for bed.

Jag går tillbaka till sängs.

English Translation

I’m going back to bed.

Why is a “s” needed at the end of the word “sängs”?

[HopOnABus]

English Translation

Get ready for bed.

https://en.m.wiktionary.org/wiki/till_sängs

I think like weird stuff in English, you just have to memorize it. Can’t find satisfactory explanation for this.

[morbrorper]

Jag går tillbaka till sängs.

It’s a remnant of the old rection system; in old Swedish, “till” used to be followed by the genitive. Now it’s only preserved in a few set expressions. These are some examples that come to mind: Till sängs. Till bords. Till havs. Till sjöss. (note the spelling) Till fots. (But: “till häst”) Till buds. Till vardags. Till lags. Till dess.