Is skill plural in this case?
I have social skill
I have social skills
social skill(s) is/are a good skill(s) to have
it's a good skill to have
they are good skill to have
"Social" and "skills" normally go together. For example, he is lacking in social skills.
"I have social skills."
"Social skills are good skills to have."
"It's a good skill to have" is OK if you are talking about one particular skill. Otherwise, "they are good skills to have" if you are referring to "social skills."
Teaching ESL to Adults