Learn Hardcore Japanese: watasi ha hasi ga zenzen tukaenakatta kedo, ima ha sugoku zyouzu da. - I couldn’t use chopsticks at all before, but now I’m very good.

With the potential form (“can/cannot”) of a transitive verb, the thing that would normally take を often takes が. Base: 箸を使う (use chopsticks). Potential: 箸が使える (can use chopsticks). Using を with a potential verb (箸を使える) is heard, especially in casual speech, but が is more common/natural and tends to emphasize the item you can’t/can use. Here, 箸が全然使えなかった = “I couldn’t use chopsticks at all.”

Could I say 箸は全然使えなかった instead?

Yes. 箸は makes “chopsticks” a contrastive topic: “As for chopsticks, I couldn’t use them (perhaps unlike other utensils).” 箸が simply marks chopsticks as the grammatical subject of the potential verb and does not add contrast. Use は if you want to contrast; use が for a neutral statement of (in)ability.

What do the は in 私は and 今は do?

は marks topics. 私は sets “me” as the topic. 今は sets “now” as a contrastive timeframe, implying “now (as opposed to before).” 今では adds a stronger “by now/as of now” nuance and is also natural: 今ではすごく上手だ.

How does 全然 work? Does it have to go with a negative?

Traditionally 全然 goes with negatives to mean “at all/not in the least”: 全然使えなかった. In modern casual speech it also appears with positives to mean “totally/absolutely” (e.g., 全然大丈夫, 全然平気), but that usage is colloquial. Place 全然 before the verb/adjective/noun phrase it modifies.

What exactly does 使えなかった mean, and how is it formed?

It’s the past negative of the potential form of 使う (to use).

Dictionary: 使う
Potential: 使える (can use)
Negative: 使えない (cannot use)
Past negative: 使えなかった (could not use) Contrast: 使わなかった = “didn’t use” (no claim about ability), not “couldn’t use.”

Is けど the same as でも or が?

All mean “but,” but differ in grammar/tone.

けど (casual) links clauses: 箸が全然使えなかったけど、今は…
が (more formal/neutral) also links clauses: 箸が全然使えなかったが、今は…
でも starts a new sentence: 箸が全然使えなかった。でも、今は… Polite variants: ですが, けれども.

Is すごく上手だ correct? I often hear すごい上手.

Standard is the adverb すごく before adjectives: すごく上手だ. Many speakers say すごい上手 in casual speech; it’s widely heard but colloquial. Safer formal alternatives: とても, 非常に. Very casual/regional: めっちゃ.

When do I use 上手だ vs 上手に?

上手だ is a predicate/adjectival: 今はすごく上手だ (“I’m very good now”).
上手に is adverbial and modifies verbs: 箸を上手に使える (“can use chopsticks skillfully”).

Should it be 上手だ or 上手になった to show improvement?

Both work, but focus differs:

今はすごく上手だ states your current level.
今はすごく上手になった highlights change (“I’ve become very good now”). After a clause about past inability, 上手になった is especially natural.

Is it okay to call myself 上手?

Grammatically yes, but Japanese tends toward modesty. Softer self‑referential options: だいぶ上手になってきました or まだまだですが、前より上手です. 得意 (“a strong area”) is another option but can sound self-promotional if overused.

Why is the first clause past (使えなかった) and the second present (上手だ)? Is that okay?

Yes. Japanese freely mixes tenses to reflect actual times: “I couldn’t use [in the past], but now I am good.” 今は reinforces the contrast.

Can I drop 私?

Often yes. Subjects are commonly omitted when clear. 私は箸が… can become simply 箸が全然使えなかったけど、今は…. In casual talk, the final だ may also drop: 今はすごく上手。 Pronouns vary by persona: 私 (neutral/formal), 僕 (casual male), 俺 (very casual male).

How would I say this politely?

私は箸が全然使えませんでしたが、今はとても上手です。
A softer connector also works: …使えませんでしたけれども、….