—Look! The lake is clean. I never throw litter into it.
—If everyone does this, it would be ________.
dirtier
the dirtiest
cleaner
the cleanest
The room is not bright enough. I need to a light on the ceiling.
The piano sounds .I want to leave now. Where is the exit(出口)?
Jack his pet dog every day. The dog must feel sad when he’s alone all day long.
--Don't touch my computer when I'm away, OK? --Sorry, .
Thanks for ________ the secret ________ me.