Distribute the first worksheet and go over vocabulary they might not know, like 'educational'.
Students write their own answers on the first line. Demonstrate on the whiteboard if possible: I didn't study Chinese this summer. (I used 'this' summer instead of 'last', because I used the activity when they got back after the break in August and it was still summer.)
Students write the questions they will ask their classmates on the second line: What didn't you do this summer?
What was something educational you did this summer? etc...
Ask students to read the questions, so they can make sure the questions are formulated correctly.
Step 3: Distribute second worksheet with boxes. Have them repeat the questions from the first worksheet after you to practice pronunciation
Students pair up with someone and ask each other the questions. They write the answers in the boxes (writing full sentences unnecessary here just notes). The worksheet has room to ask four different students. You can adjust how many partners according to how much time you have. I had the students give their answers in full sentences to practice speaking the grammar.
Step 4: Decide on either a point game (from this site), a ring toss or something fun to play for points. I used darts. Divide the class into teams. Janken to see who goes first. Check the student's (whose turn it is) worksheet and ask a question about one of the four people they interviewed. 'What did Kanon not do this summer?'
I let the students use their notes to answer. 'She didn't travel abroad this summer.' Make sure they use pronouns and 3rd person. After they can toss the darts for points or whatever game you decided on. Keep score on board and go back and forth, until hopefully each student has a turn or two.
Level: I used this with my 8th grade class and they have the 'New Horizon' textbooks, so we hadn't got to superlative yet. It was fine though and all the students were able to do it. It can also be used for Grade 9.
I left it as a word document, so you can adjust the questions and vocabulary to suit the level of your class.
Edit: I added a worksheet appropriate for Gr. 7 where they just have to make simple past questions: What did you do?/ Where did you go?/ What did you eat?/ What did you buy?/ Who did you hang out with?