Перефразируйте эти предложения, используя пассивные структуры. 1. they built the house on the left bank of the river. the house 2. they didn't wait for the train long. the train 3. you may use any of these books. any of these books 4. people should remember these simple rules. these simple rules 5. the pupils will the new words by and by. the new words 6. we can't put off our meeting. our meeding

1. The house was built on the left bank of the river. 

2. The train wasn't waited for long. (This phrase is rather awkward, I'd say. But we'll chalk this "awkwardness" up to the purposes of the exercise.)

3. Any of these books may be used.

4. These simple rules should be remembered.

5. The new words will be learnt (?) (by the pupils) by and by. (You've omitted the predicate in the original phrase. So I've taken the liberty of figuring it out myself.)  

6. Our meeting cannot be put off.