SELECT a.columna, b.columnb, c.columnc
FROM ((tablea AS a) LEFT JOIN tableb AS b ON a.id = b.id) 
LEFT JOIN tablec AS c ON a.id = c.id


--Or, without the AS syntax...
SELECT tablea.columna, tableb.columnb, tablec.columnc
FROM (tablea LEFT JOIN tableb ON tablea.id = tableb.id) 
LEFT JOIN tablec ON tablea.id = tablec.id

http://nm1m.blogspot.com/2007/10/multiple-left-joins-in-ms-access.html

In Microsoft Access, if you want to do more than one LEFT JOIN, you have to use parenthesis in the FROM clause otherwise, you get a "Missing Operator" error.

MS Access, SQL JOIN syntax for 3-way table join

SQL