The way my JTE's and I ran this, it's basically Go-Fish.
1st make groups of 3 or 4 students, give each group a deck of cards.
The point is for the students to make pairs of cards. 1 pair=1 point.
They start with 5 cards.
To get a point, they either use Can I~ or Can you~.
On their turn, if they have a pair, they can use "Can I ~." with whatever is written on the card filling the blank. Then they place the pair on the table in front of them. This ends their turn.
If they don't have a pair, they choose a card from their hand and ask the others in their group "Can you ~." (with whatever is written on that card filling the blank again).
If another person has the card, they answer "Yes.", give their card to the person who asked. The person who asked then gets that pair of cards as a point.
If no one has the same card, the person asking draws a card from the pile, and their turn ends.
If more than one person has the same card, they janken to see who gives up the card.
If they run out of cards, they draw 3 new ones to keep playing. (The point is to get the most amount of points after all, not get rid of all the cards).
I would also change some of the cards in the deck before printing, since it leads to some strange requests using "Can I/Can you~". (like: Can you go to Hokkaido. or Can you use a computer. (proper grammar, but asking something a little different than what we are aiming for here in the case of "Can you use a computer." ) )
I also ended up having to change the cards like "borrow your pen" to "borrow a pen" to avoid confusion. I only realized it after the first run through, so just edited it with a pen.