To recite or chant aloud — to say repeatedly or read aloud (e.g., sutras, mantras, poems).
朝のお勤めで僧侶たちが般若心経を唱える。
During the morning service the monks chant the Heart Sutra.
合唱団は最初にリズムを合わせてから歌詞を唱え始めた。
The choir matched their rhythm first and then began to chant the lyrics.
彼女は試験前に自分に言い聞かせるように合格を唱えていた。
Before the exam she kept repeating 'I'll pass' to herself.
To cry out or shout (e.g., slogans), often used for loud collective calls or outcries.
抗議者たちはプラカードを掲げ，『賃上げを！』と唱えながら歩いた。
The protesters marched while holding placards and chanting 'Raise wages!'.
試合会場で観客が選手の名前を唱えた。
At the match the audience shouted the player's name.
To advocate or insist on something — to publicly put forward or promote an idea, policy, or position.
彼は教育の抜本的改革を唱え続けている。
He has continued to advocate fundamental reforms in education.
その学者は人権の尊重を強く唱えている。
That scholar strongly advocates respect for human rights.
会議では新しい方針を採用すべきだと数人が唱えた。
At the meeting several people argued that the new policy should be adopted.