=> for and since 

Bài 3: Read the situations and complete the sentences.

1. It is raining. It's been raining since lunchtime. It started raining at lunchtime.

2. Ann and Sue are friends.They first met years ago. They've known each other for years.

4. Joe is ill. He became ill a few days ago. He has ... a few days.

5. Liz is married. She's been married for a year. She got ...

6. You have a headache. It started when you woke up. I've ... I woke up.

7. Sue has been in Italy for the last three weeks. She went ...

8. You've working in a hotel. You started sis months ago. I've ...

Viết chương trình và in ra màn hình các số chẵn từ 1 đến n , n là số tự nhiên nhập từ bàn phím.