" I don't want to go to school (or a friends house... any where other than home)."
"What if someone laughs at me? What if I throw up?"
"I wanted to go to soccer/dance/party, but now I don't feel good."
"What if I embarrass myself?"
"What if (fill in the blank)......"
"I don't want to sleep alone."
It's possible that your child doesn't say anything about their fears, but complains of vague physical discomfort, cries frequently, and has meltdowns or angry outbursts when they have to do anything uncomfortable or new.