You shouldn’t touch the controls if you don’t know how to operate the machine. HAD
You ____________ the controls if you don’t know how to operate the machine
HAD BETTER NOT TOUCH
It wasn’t necessary for Janet to ask for a special permit to open a clothes shop. HAVE
Janet ____________ for a special permit to open a clothes shop.
DIDN'T HAVE TO ASK
When I got home, I heard someone upstairs, so I phoned the police. But it was my older brother! NEED
I ____________ the police. The person I thought was a burglar was my older brother!
NEEDN'T HAVE PHONED
It’s a pity we didn’t go to that café. OUGHT
We ____________ to that cat café.
OUGHT TO HAVE GONE