話せなかった

could not speak, could not talk

→ 話す
話せ potential form stem (can talk) + なかっ past negative + past tense
verb · past potential Uncommon #18,174
could not speak, could not talk
JA: 緊張して、うまく話せなかった。
EN: I was nervous and couldn't speak well.
Conjugation of 話す

私は恐怖のためにひと言話せなかった

I was so scared that I couldn't say a word.

その日はうまく話せなかった

I couldn't speak well that day.

今日もうまく彼女と話せなかった

I couldn't talk to her properly again today.

彼女は疲れすぎて話せなかった

She was too tired to speak.

トムはフランス語を上手く話せなかった

Tom couldn't speak French well.

ミーチャそのとき英語が話せなかったのに彼はアメリカ人は信用できると思ってた

Although Mitya couldn't speak English at the time, he thought Americans could be trusted.

— Брат 2 (2000)

最初に会ったときトムはフランス語が話せなかった

When I first met him, Tom couldn't speak French.

最初彼は全然英語が話せなかった

At first, he couldn't speak English at all.

事故の後私たちは話せなかった

We couldn't talk after the accident.

どうしても彼女に真実を話せなかった

I just couldn't bring myself to tell her the truth.

私は日本語を話せなかった

I couldn't speak Japanese.

その知らせにショックを受けたので、彼女は話せなかった

She was so shocked by the news that she couldn't speak.