They hasnt come back to their hometown since 1989 ==> The last time..

They hasn't come back to their hometown since 1989

==> The last time they came back to their hometown  was in 1989.

+) cấu trúc:

S+ haven't/hasn't  + V-pll+for/since+tgian

-> the last time +S+V2/V-ed +was+tgian (ago)

S + has/have + not + V3/ed + for/since + time 

--> S + last + V2/ed 

--> The last time + S+ V2/ed + was + time 

--> It is / has been + time + since + S+ (last) + V2/ed 

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Đáp án: The last time they came back to their hometown was in 1989.

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