feebler , feeblest
If you describe someone or something as feeble, you mean that they are weak.
He told them he was old and feeble and was not able to walk so far.
他告诉他们,自己年老体弱,不能走那么远。
If you describe something that someone says as feeble, you mean that it is not very good or convincing.
This is a particularly feeble argument.
这是个特别站不住脚的论点。