Hey i'm new too, not quite sure what you meant but i think you say you run out of things to talk about? If that is right, try commenting on someone within the set and ask them about it eg. ( basic examples ) hey those are really nice earings where did you get them from? This invites a conversation to start etc.
I find that it is always best to as about a subject you are knowledgable in and can talk about for a long time if need be. For example I am a musician and therefore know quite a bit about music and so i would ask a girl what her favourite bands are or what music she is into. The best thing about this is you can give your own personal opinion about the topic. For example:
Me ' so what sort of music are we all into ( refer to the whole group if using this approach )'
group ' oh we like this band '
me ' oh yeah that bands good but i think the guitar work could be improved, i prefer this band '
and so on... try and adopt a common topic between you and the group. Ask their interests and if you know anything about them talk about them 1. ask question 2. say yes i like that/ agree with that but i think this is better 3. go off what they say. Good luck and hope this helps ( sorry if this post was erratic I'm really tired
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