John and I _____ friends for eight yearsWe first got to know each other at a Christmas partyBut we _____ each other a couple of times before that

____ no doubt that the Great Wall is one of the wonders of the world [ ]

People are encouraged to speak openly, but careless words are ________ to hurt others’ feelings.[ ]

I once got lost during my first visit toBeijing.– Oh, did you You ____ me as your guide.

She did the exercise again. She forgot ____ it.