These sentences were read aloud by real people — native Japanese speakers — for the open Mozilla Common Voice project. Listen to how a phrase sounds in real speech: the intonation, the pace, the way words run together. Two speakers mean two different people read it — compare them.
環境汚染はだめ
かんきょうおせんはだめPolluting the environment is not OK.
汚染は、もはや地球規模であり、人類は、その、種の存続さえ、危うくされているのだ。
おせんは、もはやちきゅうきぼであり、じんるいは、その、たねのそんぞくさえ、あやうくされているのだ。Pollution is now global in scale, and humanity's very survival as a species is threatened.