1. I don’t know much about historical events, so I can t help her with her historyhomework. (IF)

→ If I knewabout historical events, I could help her with her history homework.

2. This is the first time I have heard about the tram system in Hanoi. (NEVER)

→ I have never heard about the tram system in Hanoi before

3. Firefighters spent two hours releasing the driver from the wreckage. (IT)

→ It takes firefighters 2 hours to releasing the driver from the wrreckage

4. They took the president to the hospital for an emergency operation. (WAS)

→ The president was taken to the hospital an emergency operation

5. I had saved my document before the computer crashed. (AFTER)

→ After the computer crashed I had saved my document

6. English is necessary to learn now. (IT)

→ It's important to learn English

Xin 5 sao+ CTLHN nhaaa^^