We can summarize all this in a table:

Here, a 🟩 means a successful match, and a 🟥 means a failed match.  For those that involve variables, we also list what the variable is connected to.

Matching multiple parameters

When we match a call with multiple parameters, we just match each parameter in turn.  But since one parameter might connect a variable to a value (or another variable), it can affect the matching of other parameters.

Easy case

When we match the call [Give "Mary" "Jill" "a nice raise"] against the method:

Give ?giver ?receiver ?item: ?giver gave ?receiver ?item.

Each variable is in a different parameter, so matching is easy:

Matching between parameters

What if we match the same call against the other method:

Give ?giver ?giver ?item: ?giver gave [Reflexive ?giver] ?item

Then we have a problem.  Parameter 1 wants to connect ?giver wtih "Mary" and parameter 2 wants to connect it with "Jill". It can't do both, so the match fails:

On the other hand, the call [Give "Mary" "Mary" "a nice raise"] works fine, because both parameters want to connect ?giver to the same value:

Fancy example

Now let's match against the same method, but change the call slightly:

[Give "Mary" ?somebody "a nice raise"]

we might do this because we want to print something about Mary giving someone a raise, but we don't care about who.  This matches:

It connects the ?giver, ?somebody and "Mary" all together.

Matching summary

Here's table of the matching results between different kinds of calls and different kinds of methods.  To save space, We'll just use two parameters and name it Task: