diff --git a/pyvo/dal/scs.py b/pyvo/dal/scs.py
index 6f542509..1be32f6c 100644
--- a/pyvo/dal/scs.py
+++ b/pyvo/dal/scs.py
@@ -255,7 +255,7 @@ def describe(self):
 
 class SCSQuery(DALQuery):
     """
-    a class for preparing an query to a Cone Search service.  Query constraints
+    a class for preparing a query to a Cone Search service.  Query constraints
     are added via its service type-specific methods.  The various execute()
     functions will submit the query and return the results.
 
diff --git a/pyvo/dal/sia.py b/pyvo/dal/sia.py
index fcc9fdc2..602207bb 100644
--- a/pyvo/dal/sia.py
+++ b/pyvo/dal/sia.py
@@ -329,7 +329,7 @@ def describe(self):
 
 class SIAQuery(DALQuery):
     """
-    a class for preparing an query to an SIA service.  Query constraints
+    a class for preparing a query to an SIA service.  Query constraints
     are added via its service type-specific methods.  The various execute()
     functions will submit the query and return the results.
 
diff --git a/pyvo/dal/sla.py b/pyvo/dal/sla.py
index 90cff2e6..941b8a32 100644
--- a/pyvo/dal/sla.py
+++ b/pyvo/dal/sla.py
@@ -229,7 +229,7 @@ def describe(self):
 
 class SLAQuery(DALQuery):
     """
-    a class for preparing an query to an SLA service.  Query constraints
+    a class for preparing a query to an SLA service.  Query constraints
     are added via its service type-specific methods.  The various execute()
     functions will submit the query and return the results.
 
diff --git a/pyvo/dal/ssa.py b/pyvo/dal/ssa.py
index 720070e4..4e848b5b 100644
--- a/pyvo/dal/ssa.py
+++ b/pyvo/dal/ssa.py
@@ -290,7 +290,7 @@ def describe(self):
 
 class SSAQuery(DALQuery):
     """
-    a class for preparing an query to an SSA service.  Query constraints
+    a class for preparing a query to an SSA service.  Query constraints
     are added via its service type-specific properties and methods.  Once
     all the constraints are set, one of the various execute() functions
     can be called to submit the query and return the results.
diff --git a/pyvo/dal/tap.py b/pyvo/dal/tap.py
index 54f5adb4..ad6d2399 100644
--- a/pyvo/dal/tap.py
+++ b/pyvo/dal/tap.py
@@ -1011,8 +1011,8 @@ def fetch_result(self):
 
 class TAPQuery(DALQuery):
     """
-    a class for preparing an query to an TAP service.  Query constraints
-    are added via its service type-specific methods.  The various execute()
+    a class for preparing a query to a TAP service.  Query constraints
+    are added via service type-specific methods.  The various execute()
     functions will submit the query and return the results.
 
     The base URL for the query, which controls where the query will be sent