Embed SQL Statement In Another SQL Statement

Suppose I have an MS access database with query1 and query2. Query2 uses
query1 something like this:

Select table.* from (table left join query1 on field1=field2)

Now I want to make a change in query1 to change the behaviour of query2. But
this cannot be done in a live environment because I have to shut down the
application, make the change in the database and start the application
again. What I can do is make a query 3 in my application (instead of in the
database) that is initially does the same as query2 like this:

Select table.* from (table left join -->some SQL code to embed query1<-- on
field1=field2)

Once I know how to do this, I can change the "embedded" sql code to my
needs.

Question is: how do I "embed" SQL code in another statement?