added sentence about removal of non-labeled examples

README.md

@@ -60,6 +60,7 @@ task_ids:
 
 This is a stance prediction dataset in Chinese.
 The data is that from a shared task, stance detection in Chinese microblogs, in NLPCC-ICCPOL 2016. It covers Task A, a mandatory supervised task which detects stance towards five targets of interest with given labeled data. 
+Some instances of the dataset have been removed, as they were without label.
 
 ### Supported Tasks and Leaderboards
 
@@ -70,6 +71,7 @@ The data is that from a shared task, stance detection in Chinese microblogs, in
 Chinese, as spoken on the Weibo website  (`bcp47:zh`)
 
 ## Dataset Structure
+ 
 
 ### Data Instances