The serious situation made it possible for laws preventing pollutions_________in many countries.
--- Is your father a teacher of English in No. l Middle School? --- No. But he ______ English there for ten years.
. It is none of your business ______ other people think about you. Believe in yourself.
This advertisement is a/an______ example of their marketing strategy
We must soon ______a new teacher to the class.
The tourists, had enjoyed themselves so much in the botanic garden, were worn out