1. It was his presence at the meeting that frightened the children. 
2. It was the book that Hoa borrowed from Long.
3. It was on his birthday that she presented him a book. 
4. It is thanks to new medicines that many diseases are no longer dangerous. 
5. It is all the data that John has stored on the floppy disk.  
6. D
7. B
8. C 
9. B
10. C
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- Câu chẻ: It + be + N/adj/adv/... + that/who/... + ....
- tobe và V sau that luôn cùng thì