Ya no me olvido del cargador; llevo semanas enchufándolo por la noche.

Spanish has two standard options:

• Transitive: olvidar algo. Example: No olvido el cargador.
• Pronominal: olvidarse de algo. Example: Me olvido del cargador.

Both are correct. In Spain, olvidarse de is very common and a bit more colloquial; olvidar is a touch more formal/neutral. Your sentence uses the pronominal pattern.

Yes. Se me olvida el cargador uses the so‑called accidental or experiential construction, roughly “The charger slips my mind.”

• Ya no se me olvida el cargador is a very natural alternative.
• Me olvido del cargador puts the focus more on you as the agent; se me olvida sounds more like an unintentional/habitual lapse.

Not in standard Spain Spanish. Use either:

• Transitive: Lo olvido.
• Pronominal: Me olvido de él / de eso / del cargador.

Mixing the two into me lo olvido is nonstandard in Spain (though it occurs in some Latin American varieties).

It expresses how long you’ve been doing something: “to have been doing X for [time].”

• Structure: llevar + [length of time] + [gerund]
• Example: Llevo semanas enchufándolo = I’ve been plugging it in for weeks.

Yes. With a conjugated verb + gerund, you can place the pronoun:

• Before the conjugated verb: Lo llevo enchufando por la noche.
• Attached to the gerund: Llevo enchufándolo por la noche.

Both are correct; the difference is only rhythm/prosody.

It’s potentially ambiguous. Grammatically, lo could refer to any masculine singular noun understood from context. Since el cargador was just mentioned, one might read it as “plugging the charger in.” In everyday life, many people intend “plug the phone in.”

To avoid ambiguity, you could say:

• Llevo semanas enchufando el móvil por la noche.
• If you mean charging the phone: Llevo semanas cargándolo por la noche or Lo pongo a cargar por la noche (very natural in Spain).

In Spain:

• por la noche = at/during the night (can be generic or specific).
• por las noches = at night(s) regularly; it highlights habit more clearly.
• de noche = at night (as opposed to daytime), a bit more general.
• en la noche is much less common in Spain; it’s heard more in Latin America.

Your sentence is fine with por la noche; por las noches would also fit the habitual sense.

Both are correct:

• Llevo semanas… = for weeks (unspecified, possibly many).
• Llevo unas semanas… = for some/several weeks (sounds a bit more limited/approximate).

Yes. Llevar + sin + infinitivo means “to have gone [time] without doing [something]”:

• Llevo semanas sin olvidarme del cargador = I haven’t forgotten the charger for weeks.
  You can also use the transitive verb: Llevo semanas sin olvidarlo.

Both convey “I’ve been plugging it in for weeks,” but:

• Llevar + gerundio is very idiomatic in Spain to express accumulated duration.
• Estar + gerundio with a time phrase (e.g., He estado… durante semanas / desde hace semanas) is fine but sounds a bit more like you’re describing the activity itself rather than the span. Nuance is small; both are correct.

The semicolon separates two closely related independent clauses. You could also write:

• Period: Ya no me olvido del cargador. Llevo semanas…
• Or add y: Ya no me olvido del cargador, y llevo semanas… Using just a comma without a conjunction is less formal/standard.

A habit/change in habit: “I no longer forget the charger.”
For a single occasion you’d use a past tense, e.g.:

• Recent (Spain): No me he olvidado del cargador.
• Specific past: No me olvidé del cargador.
  Using ya no with a one-off past event is unusual.

Common options include:

• Llevo semanas cargándolo por la noche. (charging it at night)
• Lo pongo a cargar por la noche; llevo semanas así.
• Llevo semanas enchufando el móvil por la noche.