3 modals expressing "possibility"

Rewrite the following sentence: "It's certain that the thieves knew where the jewellery was".                          They ....................................... where the jewellery was.

2 modals expressing "ability" in the present

The past of the modal verb "can" is ...

Rewrite the following sentence: "It's possible that they forgot to turn on the alarm".                  They ...................to turn on the alarm.

Rewrite the following sentence: "We were ordered to empty our pockets before we could go into the concert".                                   We ........................ to empty our ....

The police ................................ find any evidence (NOT BE ABLE TO in the past)

I'm sure he ......................... be at home. He leaves work at 5 and it's 4 o'clock.

You ......................... have taken your expensive watch on a camping holiday. It was very risky.

The thief knew the secret code. It ....................... have been someone who works here.

Rewrite the following sentence: "Is it OK if I take a picture of your notes?"                             .............. I take a picture of your notes?

Rewrite the following sentence: "It was a mistake to leave my valuables in the hotel room".      I ...........................my valuables in the hotel room.

We had .................. check that the doors are locked before we go out.