I’m afraid I won’t be able to make a birthday cake.
I find this grammar very difficult to teach and make activities for.
In this attempt, I made the situation John Cena’s birthday party (He’s a pro wrestler, you can introduce him to the kids before you begin the class).
We are planning his birthday party and giving out tasks to people. First the students write their tasks in the top half of the worksheet. They can be anything. After they are all finished they walk around the class, find a partner and play Janken. The winner gives the loser a task. “I want you to … make a birthday cake”.
If the loser has it FREE (no signature next to the verb used) then they respond with a positive answer “I’m sure I’ll be able to…” and sign the winners paper next to the verb used.
BUT if the loser has a signature next to the verb that the winner used, then the loser isn’t free and needs to respond in the negative; “I’m afraid…”.
(You can give the winner 2 chances to get a signature)
Lastly, the students sit down and try and remember what they answered during the interview section. eg “I’m sure I’ll be able to make a birthday cake.”