plunge (someone/something) into something
phrasal verb with plunge verb uk/plʌndʒ/ us/plʌndʒ/
（使）陷入;（使）经历
to suddenly experience a bad situation or unhappiness, or to make someone or something suddenly experience a bad situation or unhappiness
The country was plunged into recession. 该国突然陷入经济衰退。
He was plunged into despair when his wife left him. 他妻子离开他时，他一下子陷入绝望之中。