Breakdown of Du behöver inte vattna gräsmattan så länge som det regnar.
du
you (singular)
inte
not
behöva
to need
regna
to rain
Questions & Answers about Du behöver inte vattna gräsmattan så länge som det regnar.
Is the word som required in så länge som, and does it change the meaning?
No, som is optional here. You can use both så länge and så länge som to mean "as long as" or "while". Including som can sometimes make the sentence sound a bit more complete or formal, but in everyday speech they are completely interchangeable.
Why is there no att before vattna if it translates to "to water"?
The verb behöva (to need) often acts like an auxiliary or modal verb (similar to can, must, or will) when it is followed by another verb. Because of this, it connects directly to the infinitive form vattna without needing the infinitive marker att.
What happens to the word order if I put the så länge som clause at the beginning of the sentence?
Swedish strictly follows the V2 (verb-second) rule, meaning the main verb must be the second block of information in the main clause. If you move the entire subordinate clause to the front, the main verb (behöver) must immediately follow it. The sentence becomes: Så länge som det regnar behöver du inte vattna gräsmattan.
How is the word gräsmattan built?
It is a compound noun made of gräs (grass) and mattan (the carpet or rug). So a lawn in Swedish is literally a "grass carpet"! The -n at the very end shows that it is in the definite form (the lawn).