On Halloween, children in America like to _____ as ghosts to frighten people. [ ]

.The fresh water in Canada has one-third of the world’s total, much of ____ is in the Great Lakes.

Safety regulations are being________by company managers in the drive to increase profits. That’s why the accident happened.[ ]

Tony, are you listening to me ？——Sorry sir, I to understand what you said just now

There is __________ “c” and _______“l” in the word “colour”. an, an