>>means i posted something on group

Which tools are you using to add content to your group?
From your screen shot I can guess that it is forum, but I am not sure.

"Groups" plugin uses standard Oxwall's communication tools: newsfeed, wall, forum.
Only newsfeed allows adding comments to initial posts.

Ya i am saying that there is  no  way to comment ,,means how to add newsfeed to group .

Same cuestion, how to add a comment in the group, in the demo i see demo content there but if a user want to comment comething on a group how they do that i dont find where do that :(

I agree. This feature should be added. 

Reply feature would be a huge bonus to Groups. :)

I had this problem during deployment of the website It could be that your groups module has not installed properly, if you are able disable and deactivate the plugin then install again. 

Or it could be that the newsfeed settings have disabled comments

lastly it could be that the user role could not allow comments on newsfeed

Comments are available only within the newsfeed widget in "Groups" plugin.
If you don't see "Newsfeed" widget, try activating and deactivating both "Newsfeed" and "Groups" plugins as suggested by Shane.

Our members had the same need (to like and comment posts). But Newsfeed was not available. Deactivation and activation of both Newsfeed and Groups solved the problem. Now we have replaced the Wall by Newsfeed.

But now our members complain that they are not being notified anymore when other members make posts in the Newsfeed of the Groups where they are member of.

Is there a way to activate notifications also for posts in the Newsfeed?