Answer:
I am of several different kinds, but the one you pick doesn't do its job. What am I?
The letter S is added to pluralise most words in the English language. eg. Letter to Letters Word to Words and Language to Languages. But I am a word that is pluralised with the addition of the letter C.
I always murmur but never talk. Always run but never walk. I have a bed but never sleep, have a mouth but never speak. What am I?
I am Invisible Man's drink at snack time
If it’s information you seek, come and see me. If it’s pairs of letters you need, I have consecutively three. What am I?
Almost everyone needs it, asks for it, gives it. But almost nobody takes it.
What am I?
Animal
Difficult
Easy
Food
Funny
Kids
Logic