5. Viết lại câu. 1. I was walking home when it started to rain. While I 2. When did you buy that bag? How long 3. You don't have to finish the work by Saturday. It isn't necessary 4. She's always nervous when she takes an exam. Taking 5. I want to work as an interpreter in the future. I am studying Russian at university. (dùng ‘so ‘viết lại câu)