Hi !!
I think something is missing in your choices
Some people / are / kind / to others. â–º S - Â LV - PA
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subject        = some people
linking verb    = are
predicate adjective = kind
to others       = IO (indirect object)
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S- V - IO - DO  ==> "kind" isn't an Indirect Object; "to others" isn't a   direct object
S - V - DO Â => "kind to others" isn't only a direct object
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Hope I'm right ☺☺☺