diff --git a/Makefile b/Makefile
index 650958ae..2210a682 100644
--- a/Makefile
+++ b/Makefile
@@ -18,9 +18,12 @@ deps:	## install 🐸 requirements.
 	pip install -r requirements.txt
 
 test:	## run tests.
-	nosetests -x --with-cov -cov  --cover-erase --cover-package TTS tests --nologcapture
+	nosetests -x --with-cov -cov  --cover-erase --cover-package TTS tests --nologcapture --with-id
 	./run_bash_tests.sh
 
+test_failed:  ## only run tests failed the last time.
+	nosetests -x --with-cov -cov  --cover-erase --cover-package TTS tests --nologcapture --failed
+
 style:	## update code style.
 	black ${target_dirs}
 	isort ${target_dirs}