1. This is the first time Hoang has gone abroad.
-> Hoang hasn't gone abroad before.

2. Van Anh started driving 1 month ago.
-> Van Anh has been driving for 1 month.

3. My family began eating when it started to rain.
-> My family has been eating since it started to rain.

4. I last had my hair cut when he left me.
-> I haven't had my hair cut since he left me.