If you're not sure how to go about following the guidelines in providing a thoughtful opinion, or a relevant statement/question about a link (article or audio/video) that you believe is worth sharing with the group, here are some tips.
First, ask yourself what your own view is of whatever your link is talking about. Do you like what it says, or dislike it, and why? Try writing a short statement on what you liked or disliked about whatever your link is saying, and why you liked or disliked it.
Second, ask yourself what you imagine members of the group might want to discuss about the link you want to share. What is your link saying that's worth discussing? Try writing a short statement about any key points you think the link makes, and why you think they are so important, or should be, to yourself and others.
Third, ask yourself if you have any views that could be added to whatever your link is talking about. For example, if you want to share an article that talks about specific economic causes of some event, maybe it occurs to you that there are some significant non-economic factors that the author didn't address. Try writing a short statement on any other relevant insights you have that could be added to whatever your link is saying.
Fourth, after considering and writing a short statement on
1) your own opinion of whatever the link is saying, why you liked or disliked it, and
2) what the key points are that you think others should notice and discuss about whatever your link is saying, and
3) whether there's anything else you might have to add that's significant to whatever the link is saying,
then 4) try writing a discussion-provoking question related to the key points, and/or your opinion and reasons for it, and/or any additional insights you might have on the topic
Of course, providing your thoughtful opinion, or a relevant statement or question about your link needn't involve ALL these things together, but if you're not sure how to go about providing such a thing with your link, following these steps should help.
As you can see, providing a thoughtful opinion, or a relevant statement/question about a link (article or audio/video) is all a matter of simply engaging the material for yourself before asking others to. It's like the golden rule.