Composite readings

Composite Mercury to the Ascendant

A composite chart is built from the midpoints between two people's charts, so it is one chart for the pair rather than a chart for either person. These readings say what a placement in it stands for in a pair's shared chart.

Together

Composite Mercury conjunct with the Ascendant
Talk and ideas are part of the pair's outward manner, so the way it thinks and the way it speaks are close to the same thing: questions and observations come naturally to it.
Composite Mercury in an easy aspect with the Ascendant
The pair's thinking supports its outward manner, so ideas tend to be put in a tone that suits the moment and explaining itself comes with little strain.
Composite Mercury in a hard aspect with the Ascendant
The pair's way of reasoning and its outward manner differ in pace and style, so what it says may not match the impression it gives.

None of this is a verdict. A single placement never describes a whole relationship, and astrology is a tradition of interpretation rather than a body of established fact.