Answer:
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 have a frame but no picture. I have poles but not standing up
When I am alive, people sing. When I am dead, people clap hands. What am I?
If you drop me I'm sure to crack but give me a smile and I'll always smile back. What am I?
I look at you, you look at me. I raise my right, you raise your left. What am I?
I flow from the Homerβs mouth when he sees doughnuts.