He was indescribably happy. 他那个高兴劲儿,就别提了。
You can hardly imagine what a hard time your mother had when she was a child. 你妈妈小时候别提有多苦了。
牛津高阶第八版
美国韦氏词典
Dictionary.com
Free Dictionary
维基百科 (自由的百科全书)