'Tends' in the Bible

Now as to things which have been sacrificed to idols. This is a subject which we already understand--because we all have knowledge of it. Knowledge, however, tends to make people conceited; it is love that builds us up.

Who at any time serves as a soldier at his own expense? Who plants a vineyard and does not eat the fruit of it? Or who tends a flock and does not use the milk of the flock?