[minsoo325]

Dear Mike

I was doing Basic Setup Drill Set 1 on p.140 #2 and I cannot fully understand how “Exactly one plane departs after N but before R” turns in to N_RS or NSR.
Doesnt it mean that there will be exactly one space after N? Then, How could _RS & SR attach after N?
Please let me know! Thank you!

[Mike Kim]

Hi Min —

Exactly one plane after N and before R means that there is exactly one other element that goes in between N and R, going after N and before R — since we don’t know what that one element is, we can notate the rule like so:

N _ R

The final rule gives us SR or RS.

If we combine those rules, when S goes immediately before R, S must be the one element that fits in between N and R, like so: NSR.

When S goes immediately after R, we can notate the combination of rules like so: N _ RS

Hope that clears it up and let me know if you have any follow-up q’s — Mike