Structures
Unit 1
Revising useful structures--- Infinitives
Exercise
He discovered how ___________ the   door.  (open)2. I found out where __________ fruit   cheaply.  (buy)3. I didn’t know when __________ the machine off.  (switch)4. I showed her which button __________.      (press)5. She couldn’t think what _________.(say)
to open
to buy
to switch
to press
to say