$\text{3.}$
$\text{→}$ The last time I met him was 10 years ago.
$\text{→}$ I last met him 10 years ago.
$\text{→}$ It is 10 years since I last met him.
$\text{4.}$
$\text{→}$ The last time I spoke to her was 3 years ago.
$\text{→}$ She last spoke to me 3 years ago.
$\text{→}$ I haven't spoken to her for 3 years.
$\text{5.}$
$\text{→}$ The last time he came back his home village was 5 months ago.
$\text{→}$ He hasn't come back his home village for 5 months.
$\text{→}$ It is 5 months since he last came back his home village.
* Form:
- S + have/ has + not + Ved/ P2 + for/ since.
$\text{=}$ The last time S + Ved/ P1 + was + time.
$\text{=}$ S + last + Ved/ P1 + time.
$\text{=}$ It is + time since + S + last + Ved/ P1.