Learn Hardcore German: Ich habe schon die Lampe eingeschaltet, damit wir alles gut sehen können. - I have already switched on the lamp so that we can see everything well.

German’s Perfekt is built with an auxiliary (usually haben or sein) plus a past participle. Transitive verbs like einschalten always take haben. For separable verbs, the past participle is formed by attaching ge‑ between the prefix and the stem:
• Prefix: ein-
• Ge- + stem: ge‑schaltet
→ eingeschaltet
Hence: ich habe die Lampe eingeschaltet.

Where does the separable prefix ein‑ go in the past participle eingeschaltet?

In finite present-tense forms you split it (“ich schalte … ein”), but in the past participle it reunites with the stem around ge-:
ein‑ + ge‑ + schaltet → eingeschaltet.

What does schon add to the sentence, where can it appear, and can I replace or omit it?

schon means “already.”
  • Placement: In a Perfekt clause, the finite verb (habe) is #2, so schon often follows it:
    Ich habe schon die Lampe eingeschaltet.
    You can also place schon after the object:
    Ich habe die Lampe schon eingeschaltet.
    Or even at the very beginning for emphasis:
    Schon habe ich die Lampe eingeschaltet.
  • Replacement: You can use the more formal synonym bereits.
  • Omission: Dropping schon is grammatically fine (Ich habe die Lampe eingeschaltet), but you lose the sense that it was done “already.”

Why is there a comma before damit?

damit is a subordinating conjunction introducing a purpose clause. In German, subordinate clauses are always set off by a comma.

Why do we use damit wir alles gut sehen können instead of um … zu?

Use damit when the subject of the main clause differs from that of the subordinate clause. Here, main clause subject = ich, subordinate clause subject = wir. um … zu requires the same subject in both clauses.

Why does können appear at the end of the subordinate clause, and why is it sehen können rather than können sehen?

In a subordinate clause the finite verb moves to the very end. With a modal construction, the non‑finite main verb (sehen) precedes the finite modal (können), so you get:
…, damit wir alles gut sehen können.

Can I replace damit with sodass in this sentence?

Yes, but the nuance differs:
• damit expresses purpose (“so that [in order to] we can see”).
• sodass expresses result (“such that as a result we can see”).
Grammar and word‐order behave the same, but sodass focuses on what happened, not on the intended goal.

Can I put the purpose clause damit wir alles gut sehen können at the very beginning of the sentence?

Absolutely. You’d write:
Damit wir alles gut sehen können, habe ich schon die Lampe eingeschaltet.
After a fronted subordinate clause, the main clause begins with the finite verb (habe), as in any V1 structure.

What case is die Lampe, and why?

die Lampe is in the accusative case because it’s the direct object of the transitive verb einschalten. In singular feminine, the accusative article remains die.