Ask the Experts / A problem about sittable bench

Guys,I need some help! I just had a look at some NE parks and discovered that some sittable benches put on the invisible path.But I couldn't do this.When I tried to put them on the invisible path,there's no any bench there.

Enable "height marks on path" and then mouse over the height marker when trying to place path items.  This should work 90% of the time.

Enable "height marks on path" and then mouse over the height marker when trying to place path items.  This should work 90% of the time.

Thanks, the problem has solved.