How to find all users who comment all the articles commented by a given user?

Question

I have following problem in my HW.

List the userID, username and last login date of user/s who comment all the articles commented by a given user. (given userID)

This is my table format:

user(userID:char(10), username:char(30), registrationDate:date,lastLoginDate:date),
article(articleID:char(10), userID:char(10), name:char(80), description:char(130), date:date, rating:int),
comment(commentID:char(10), articleID:char(10), userID:char(10), message:char(130), date:date, rating:int),

I have tried the following query to find people who comment all the articles commented by a given user. For example, the given user id is U102;

select C.articleID,U.userID, U.username, U.LastLoginDate from user U, comment C where U.userID = C.userID AND C.articleID IN (select articleID from comment where userID= 'U102');

Then following is my output here:

+-----------+--------+----------------+---------------+
| articleID | userID | username       | LastLoginDate |
+-----------+--------+----------------+---------------+
| A105      | U101   | Jon Skeet      | 2016-11-29    |
| A105      | U102   | Darin Dimitrov | 2016-11-28    |
| A104      | U105   | VonC           | 2016-11-25    |
| A104      | U101   | Jon Skeet      | 2016-11-29    |
| A104      | U102   | Darin Dimitrov | 2016-11-28    |
+-----------+--------+----------------+---------------+

However, this is not what I want. What I expect is :

+-----------+--------+----------------+---------------+
| articleID | userID | username       | LastLoginDate |
+-----------+--------+----------------+---------------+
| A105      | U101   | Jon Skeet      | 2016-11-29    |
| A105      | U102   | Darin Dimitrov | 2016-11-28    |
| A104      | U101   | Jon Skeet      | 2016-11-29    |
| A104      | U102   | Darin Dimitrov | 2016-11-28    |
+-----------+--------+----------------+---------------+