This is already found in:
He presented a feeble argument in defence of his views.
She gave a feeble excuse for missing her appointment.
Influenza has left him very feeble.
The pre-dawn light was very feeble.
Her voice was so feeble it was difficult to hear.
The old man was so sick that he was to feeble to get out of bed.
Your feeble attempt at revenge will not go unanswered.
The word "feeble" is an adjective.
The blending word for "feeble" and "debility" is "feebility."
He presented a feeble argument in defence of his views. She gave a feeble excuse for missing her appointment. Influenza has left him very feeble. The pre-dawn light was very feeble. Her voice was so feeble it was difficult to hear.
I am not writing a sentence using that word.
a sentence using the word endotracheal
This is a sentence using the word aviator.
The robber had to languish in prison for his crimes.
I am saying a sentence using the word collagen.
this is a sentence using the word armchair.
feeble, weak, puny, infirm, flimsy, delicated, vulnerable, insubstantial