He is honest and warm-hearted. __________ is why we trust him.
When I offered to take Jane to the ancient town, she asked what _____ to see there
_____ wants to may come to the party on Saturday night.
It is in the room _____my father was born in 1932. _____ I was born.
Shanghai is no longer _____ it was fifty years ago.
The modern plane is not the machine _____ it was when first invented.