<!--
If your issue is a usage or a general question, please submit it here instead:
- Mailing List: https://groups.google.com/forum/#!forum/gensim
For more information, see Recipes&FAQ: https://github.com/RaRe-Technologies/gensim/wiki/Recipes-&-FAQ
-->

<!-- Instructions For Filing a Bug: https://github.com/RaRe-Technologies/gensim/blob/develop/CONTRIBUTING.md -->

#### Description
TODO: change commented example
<!-- Example: Vocabulary size is not what I expected when training Word2Vec. -->

#### Steps/Code/Corpus to Reproduce
<!--
Example:
```
from gensim.models import word2vec

sentences = ['human', 'machine']
model = word2vec.Word2Vec(sentences)
print(model.syn0.shape) 
```
If the code is too long, feel free to put it in a public gist and link
it in the issue: https://gist.github.com
-->

#### Expected Results
<!-- Example: Expected shape of (100,2).-->

#### Actual Results
<!-- Example: Actual shape of (100,5). 

Please paste or specifically describe the actual output or traceback. -->

#### Versions
<!--
Please run the following snippet and paste the output below.
import platform; print(platform.platform())
import sys; print("Python", sys.version)
import numpy; print("NumPy", numpy.__version__)
import scipy; print("SciPy", scipy.__version__)
import gensim; print("gensim", gensim.__version__)
from gensim.models import word2vec;print("FAST_VERSION", word2vec.FAST_VERSION)
-->


<!-- Thanks for contributing! -->