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interrogative; P. and V. τίς;
indirect: P. and V. ὅστις.
relative: P. and V. ὅς, ὅστις, ὅσπερ.
which of two, interrogative: P. and V. πότερος;
indirect: P. and V. ὁπότερος.
in which of two ways, interrogative: P. ποτέρως; indirect: P. ὁποτέρως.