Speakers may be unable to sustain speech to complete the task and may rely heavily on repetition of the prompt.

发言者可能无法持续讲话来完成任务，并严重依赖反复提示。

youdao

She seemed to be unable to rouse herself to do anything.

她似乎打不起精神做任何事情。

《柯林斯英汉双解大词典》

She will be unable to attend because of a prior engagement.

因事先有别的安排，她将不能出席。

《牛津词典》

People can also be unable to perform the simple activities of daily living without assistance because of the severe myofascial pain.

VOA: special.2011.07.26

Now,looking at the situation from the outside, Shelly Kagan we might be unable to tell which one is really Shelly Kagan.

现在，从外部看一下这个情形，我们也许无法说出谁才是。

耶鲁公开课 - 死亡课程节选

And to be dead then, is to be unable to engage in P-functioning.

而死亡就是，失去了人格功能性。

耶鲁公开课 - 死亡课程节选

The fear they will be unable to support themselves let alone if they have children.

FORBES: Readers Say

Consequently, Amazon may be unable to begin the manufacturing process in June as originally anticipated.

FORBES: Amazon's First Smartphone Held Up By Supply Chain Issues

However, academic problems don't necessarily mean a person with dyslexia will be unable to succeed.

CNN: Dyslexia