I'm not sure how, but some setting has changed in my Solidworks.  I used to be able to freely drag a line around after I sketched it.  Now, when I draw, say, a vertical line, I can only move it horizontally.  It's like the end-points are fixed in the y-direction.  If i click on the endpoints, I can move the line around (but the other endpoint will stay in the same y-position.  How do I fix this so that I can click/drag a line around anywhere I want?