1: I began living in Ho Chi Minh city when I was 8
=> I have living in Ho Chi Minh city since I was 8.
2: She has taught the children in this remote village for five months
=> She started teaching the children in this remote village five months ago.
3: Samuel stared keeping a diary in 1997
=> Samuel has kept a diary since 1997.
4: This is the first time he went abroad
=> He hasn't gone abroad before.
5: It takes me 2 hours to finish my homework
=> I spend 2 hours finishing my homework.
~Mila~
Cho mình xin hay nhất nhoa bn!^^