`1.`  Tom hasn’t come back to his hometown for 5 years.

`->` S + have/has + not + Vpp + for/since + time

`=` The last time + S + V2/ed + was + time + ago

`2.` He has worked as a teacher for 6 months.

`->` S + have/has + Vpp + for/since + time

`=` S + started/began + V-ing + time + ago

`3.` We haven't gone to Japan for 3 years.

 S + have/has + not + Vpp + for/since + time

`=` It is + time + since + S (first) + V2/ed

`4.` I haven’t had my hair cut since June.

`->` S + have/has + not + V3/ed + for/since + time

`=` S + last + V2/ed + time + ago

`5.` We haven't met for 2 years.

`->` S + have/has + not + Vpp + for/since + time

`=` The last time + S + V2/ed + was + time + ago

`6.` We have not called each other for a long time.

`->` S + have/has + not + Vpp + for/since + time

`=` The last time + S + V2/ed + was + time + ago

`7.` How long have you had 10 scores in Math?

`->` How long + have/has + S + V3/ed?

`=` When + did + S  + V?

`8.` I have never had such an exciting trip.

`->` S + have + never + Vpp + such + a/an + adj + Noun

`=` This is the first time + S+ have/has + V3/ed + such + a/an + adj + Noun

`9.` The last time I saw Anna was 10 days ago.

`->` S + have/has + not + Vpp + for/since + time

`=` The last time + S + V2/ed + was + time + ago

`10.` It is three days since I (last) took a bath.

 S + have/has + not + Vpp + for/since + time

`=` It is + time + since + S (last) + V2/ed