diff --git a/025-factorize.dfy b/025-factorize.dfy
index 6ea82bc..963e376 100644
--- a/025-factorize.dfy
+++ b/025-factorize.dfy
@@ -24,16 +24,16 @@ method factorize(n: nat) returns (factors: seq<nat>)
   {
     ghost var pre := cur;
     ghost var temp := 1;
-    while cur % i == 0 
+    while cur % i == 0
       // invariants-start
       invariant cur >= 1
       invariant temp * cur == pre
-      invariant prod(factors) == taken * temp 
+      invariant prod(factors) == taken * temp
       // invariants-end
       decreases cur - 1
     {
       factors := factors + [i];
-      
+
       cur := cur / i;
       temp := temp * i;
       assert 2 <= i && 2 * cur <= i * cur; // assert-line
@@ -47,4 +47,4 @@ method factorize(n: nat) returns (factors: seq<nat>)
   }
   assert taken == n; // assert-line
   // impl-end
-}
\ No newline at end of file
+}
diff --git a/037-sort_even.dfy b/037-sort_even.dfy
index dee0660..a939f7b 100644
--- a/037-sort_even.dfy
+++ b/037-sort_even.dfy
@@ -1,13 +1,13 @@
-method sorted_even(a: seq<int>) returns (sorted_even: seq<int>)
+method sorted_even(a: seq<int>) returns (sorted: seq<int>)
   // pre-conditions-start
   requires |a| > 0
   // pre-conditions-end
   // post-conditions-start
-  ensures |sorted_even| == |a|
-  ensures forall i, j :: 0 <= i < j && 2 * i < |sorted_even| && 2 * j < |sorted_even| ==>
-      sorted_even[2 * i] <= sorted_even[2 * j]
-  ensures forall i :: 0 <= i < |a| && i % 2 == 1 ==> sorted_even[i] == a[i]
-  ensures multiset(a) == multiset(sorted_even)
+  ensures |sorted| == |a|
+  ensures forall i, j :: 0 <= i < j && 2 * i < |sorted| && 2 * j < |sorted| ==>
+      sorted[2 * i] <= sorted[2 * j]
+      ensures forall i :: 0 <= i < |a| && i % 2 == 1 ==> sorted[i] == a[i]
+      ensures multiset(a) == multiset(sorted)
   // post-conditions-end
 {
   // impl-start
@@ -24,7 +24,7 @@ method sorted_even(a: seq<int>) returns (sorted_even: seq<int>)
     i := i + 1;
   }
 
-  sorted_even := SortSeqPred(a, p);
+  sorted := SortSeqPred(a, p);
   // impl-end
 }
 
diff --git a/073-smallest_change.dfy b/073-smallest_change.dfy
index c2909c2..999eb1a 100644
--- a/073-smallest_change.dfy
+++ b/073-smallest_change.dfy
@@ -1,6 +1,6 @@
 method smallest_change(s: seq<int>) returns (c: int)
   // post-conditions-start
-  ensures c == |set i {:trigger s[i]} | 0 <= i < |s| / 2 && s[i] != s[|s| - 1 - i]|
+  ensures c == |set i | 0 <= i < |s| / 2 && s[i] != s[|s| - 1 - i]|
   // post-conditions-end
 {
   // impl-start
diff --git a/087-get_row.dfy b/087-get_row.dfy
index b5d628d..1e46bb3 100644
--- a/087-get_row.dfy
+++ b/087-get_row.dfy
@@ -1,4 +1,6 @@
-method get_row(lst: seq<seq<int>>, x: int) returns (pos: seq<(int, int)>)
+type SortSeqState = seq<(int, int)>
+
+method get_row(lst: seq<seq<int>>, x: int) returns (pos: SortSeqState)
   // post-conditions-start
   ensures forall i :: 0 <= i < |pos| ==> (
     var (a, b) := pos[i];
@@ -50,7 +52,7 @@ method get_row(lst: seq<seq<int>>, x: int) returns (pos: seq<(int, int)>)
     assert forall i, j :: 0 <= i < |lst| && 0 <= j < |lst[i]| && lst[i][j] == x ==> (i, j) in multiset(pos);
   }
   // assert-end
-  
+
   // assert-start
   assert forall i :: 0 <= i < |pos| ==> (
     var (a, b) := pos[i]; 0 <= a < |lst| && 0 <= b < |lst[a]| && lst[a][b] == x
@@ -71,7 +73,7 @@ function less_eq(a: (int, int), b: (int, int)): bool {
   (x == u && y == v) || less(a, b)
 }
 
-method SortSeq(s: seq<(int, int)>) returns (sorted: seq<(int, int)>)
+method SortSeq(s: SortSeqState) returns (sorted: SortSeqState)
   // post-conditions-start
   ensures forall i, j :: 0 <= i < j < |sorted| ==> less_eq(sorted[i], sorted[j])
   ensures |sorted| == |s|
diff --git a/095-check_dict_case.dfy b/095-check_dict_case.dfy
index 01662c7..858f457 100644
--- a/095-check_dict_case.dfy
+++ b/095-check_dict_case.dfy
@@ -8,7 +8,9 @@ predicate IsUpperCase(s: string)
   forall i :: 0 <= i < |s| ==> 'A' <= s[i] <= 'Z'
 }
 
-method CheckDictCase(dict: map<string, string>) returns (result: bool)
+type DictCase = map<string, string>
+
+method CheckDictCase(dict: DictCase) returns (result: bool)
   // post-conditions-start
   ensures dict == map[] ==> !result
   ensures result ==> (forall k :: k in dict ==> IsLowerCase(k)) || (forall k :: k in dict ==> IsUpperCase(k))
diff --git a/105-by_length.dfy b/105-by_length.dfy
index 43625d9..d44a1b6 100644
--- a/105-by_length.dfy
+++ b/105-by_length.dfy
@@ -2,7 +2,7 @@ method SortReverseAndName(arr: seq<int>) returns (result: seq<string>)
   // post-conditions-start
   ensures |result| <= |arr|
   ensures forall i :: 0 <= i < |result| ==>
-    result[i] in {"One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine"}
+    result[i] in ["One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine"]
   // post-conditions-end
 {
   // impl-start