Learn Hardcore Japanese: watasi ha denki wo tukemasu.

In Japanese the typical word order is Subject–Object–Verb (SOV). So you put 私 (the topic/subject) first, 電気 (the object) next, and the verb つけます last.

What is the role of は in this sentence?

は is the topic particle. It marks 私 as “the thing we’re talking about.” It doesn’t mark the subject in a strict grammatical sense (that’s が), but it frames 私 as the context for the rest of the sentence (i.e. “As for me…”).

Why is 電気 followed by を?

を is the direct‐object marker. The verb つけます (to turn on) is transitive, so it needs a direct object. 電気をつけます literally means “turn on the electricity/light.”

What form is つけます, and how does it relate to つける?

つけます is the polite, non‐past form of the verb whose dictionary form is つける (“to turn on”). In casual speech you’d use つける for non‐past and つけた for past; in polite speech you use つけます (non‐past) and つけました (past).

Is つけます present tense or future tense?

Japanese non‐past verbs cover both present habitual actions and future actions. So つけます can mean “I turn on…” (habitually) or “I will turn on…” depending on context.

Do I have to use 私 here, or can I drop it?

You can usually omit 私, since Japanese often leaves out pronouns when the subject is clear. Simply saying 電気をつけます still means “(I) turn on the light.”

What’s the difference between 電気をつける and 電気がつく?

電気をつける is the transitive form (“to turn on the light” – someone does it).
電気がつく is the intransitive form (“the light comes on” – it happens by itself).
Japanese often uses such transitive/intransitive verb pairs.

Does 電気 mean “electricity” or “light”?

Literally 電気 means “electricity,” but in everyday conversation it refers to the lamp or light itself. So 電気をつける naturally means “turn on the light.”

How do I say “I turned on the light” in past tense?

Use the polite past form つけました.
電気をつけました。
This means “I turned on the light.”