How to connect multiple points to a rec2pt?

I’ve been using GH for lots of things and I’ve often been confused by the data structure so I’m very glad to be working through the Essential Algorithms and Data Structures by Rajaa Issa. But I’m getting stuck on trying Simple Tree operations turtorial #2 because it shows 4 points going into a Rec2Pt input B. I started the thing (5.8 KB)
Every time I try to connect more than one point to B, the previous one disappears. It only wants to accept one. I’m feeling stupid. Is there something basic I’m missing? Help.

You need to hold the shift key to add additional inputs to a node which already has an input.

In grasshopper go to Help > Tutorial Files. Go through all those first before you start using Grasshopper.

This is in Tutorial File 3:

Wonderful. All these little hidden things. Thank you both.
I started using GH before the tutorials so I haven’t paid much attention to them.