unable to express feelings or ideas clearly, or expressed in a way that is difficult to understand

When it comes to expressing their emotions, some people are hopelessly inarticulate. 一些人在表达自己的感情时显得笨嘴拙舌。

His speech was inarticulate and it was obvious he had been drinking. 他讲话口齿不清，很明显他喝酒了。

Opposite: articulate