If there is an auxiliary verb in the sentence, then use that as the verb in the tag (as in number 2).
If there isn�t an auxiliary verb in the sentence, then use the auxiliary verb that you would use for a negative.
If the main verb of the sentence is a form of "be", then use that verb in the tag.
For number 1, you have "People have few friends" (not friend). The negative would be "People don�t have few friends", so we use "don�t" in the tag.
Unfriendly people have few friends, don�t they?
Number 2 has the verb is "is", so we use that in the tag.
It is unpleasant to be in a strange country, isn�t it?
Bruce