diff --git a/src/api/python/z3/z3.py b/src/api/python/z3/z3.py
index 809e32644..978141de9 100644
--- a/src/api/python/z3/z3.py
+++ b/src/api/python/z3/z3.py
@@ -9873,6 +9873,14 @@ def String(name, ctx=None):
     ctx = _get_ctx(ctx)
     return SeqRef(Z3_mk_const(ctx.ref(), to_symbol(name, ctx), StringSort(ctx).ast), ctx)
 
+def SubString(s, offset, length):
+    """Extract substring or subsequence starting at offset"""
+    return Extract(s, offset, length)
+
+def SubSeq(s, offset, length):
+    """Extract substring or subsequence starting at offset"""
+    return Extract(s, offset, length)
+
 def Strings(names, ctx=None):
     """Return a tuple of String constants. """
     ctx = _get_ctx(ctx)
diff --git a/src/smt/smt_solver.cpp b/src/smt/smt_solver.cpp
index 378e56314..d282a59da 100644
--- a/src/smt/smt_solver.cpp
+++ b/src/smt/smt_solver.cpp
@@ -88,12 +88,18 @@ namespace smt {
             smt_solver * result = alloc(smt_solver, m, p, m_logic);
             smt::kernel::copy(m_context, result->m_context);
 
-            for (auto & kv : m_name2assertion) 
-                result->m_name2assertion.insert(translator(kv.m_key),
-                                                translator(kv.m_value));
 
             if (mc0()) 
                 result->set_model_converter(mc0()->translate(translator));
+
+            for (auto & kv : m_name2assertion) { 
+                expr* val = translator(kv.m_value);
+                expr* t = translator(kv.m_key);
+                result->m_name2assertion.insert(t, val);
+                result->solver_na2as::assert_expr(val, t);
+                m.inc_ref(val);
+            }
+
             return result;
         }
 
diff --git a/src/solver/combined_solver.cpp b/src/solver/combined_solver.cpp
index 538fa6296..6ce8a6ae0 100644
--- a/src/solver/combined_solver.cpp
+++ b/src/solver/combined_solver.cpp
@@ -59,7 +59,8 @@ private:
     ref<solver>          m_solver2;
     // We delay sending assertions to solver 2
     // This is relevant for big benchmarks that are meant to be solved
-    // by a non-incremental solver. 
+    // by a non-incremental solver.                                                 );
+
     bool                 m_solver2_initialized;
 
     bool                 m_ignore_solver1;
@@ -137,6 +138,7 @@ public:
     }
 
     solver* translate(ast_manager& m, params_ref const& p) override {
+        TRACE("solver", tout << "translate\n";);
         solver* s1 = m_solver1->translate(m, p);
         solver* s2 = m_solver2->translate(m, p);
         combined_solver* r = alloc(combined_solver, s1, s2, p);