Update README.md

Author: anupriyatripathi

README.md

@@ -209,5 +209,5 @@ qiime empress community-plot \
     --o-visualization empress-tree.qzv
 ```
 
-The output empress QZV can be visualized in using [Qiime2 Viewer](https://view.qiime2.org); EMPress can be used to interactively modify the tree visualization. 
+The output empress QZV can be visualized using [Qiime2 Viewer](https://view.qiime2.org); EMPress can be used to interactively modify the tree visualization. 
 For example, if the user has sample metadata columns to compare groups of samples, Empress enables them to visualize feature abundance barcharts at the tips of the tree (abundance or relative abundance) of the feature stratified by the sample metadata column of interest. Please visit [Empress tutorial](https://github.com/biocore/empress) for all the currently supported tree visualization features that can be leveraged to explore the chemical diversity of your metabolomics dataset.