diff --git a/spacy/cli/ud_train.py b/spacy/cli/ud_train.py
index 86fdabca4..7048d748b 100644
--- a/spacy/cli/ud_train.py
+++ b/spacy/cli/ud_train.py
@@ -124,13 +124,16 @@ def read_conllu(file_):
     return docs
 
 
-def _make_gold(nlp, text, sent_annots):
+def _make_gold(nlp, text, sent_annots, drop_deps=0.0):
     # Flatten the conll annotations, and adjust the head indices
     flat = defaultdict(list)
+    sent_starts = []
     for sent in sent_annots:
         flat['heads'].extend(len(flat['words'])+head for head in sent['heads'])
         for field in ['words', 'tags', 'deps', 'entities', 'spaces']:
             flat[field].extend(sent[field])
+        sent_starts.append(True)
+        sent_starts.extend([False] * (len(sent['words'])-1))
     # Construct text if necessary
     assert len(flat['words']) == len(flat['spaces'])
     if text is None:
@@ -138,6 +141,12 @@ def _make_gold(nlp, text, sent_annots):
     doc = nlp.make_doc(text)
     flat.pop('spaces')
     gold = GoldParse(doc, **flat)
+    gold.sent_starts = sent_starts
+    for i in range(len(gold.heads)):
+        if random.random() < drop_deps:
+            gold.heads[i] = None
+            gold.labels[i] = None
+
     return doc, gold
 
 #############################