“被勒索”常见的英文表达是 be blackmailed 或 be extorted（侧重于被强迫交出财物等）。
be blackmailed：
例句：He was blackmailed into giving away all his savings.（他被勒索，交出了所有的积蓄。 ）
be extorted：
例句：The company was extorted a large sum of money.（这家公司被勒索了一大笔钱。 ）