$\text{1.}$ had left - arrived

$\text{2.}$ wondered - would left

$\text{3.}$ didn't leave - had finished

$\text{4.}$ had entered - began

$\text{5.}$ asked - didn't do

$\text{6.}$ had already sent - realized - sent

$\text{7.}$ had gone - had

$\text{8.}$ was - expectd

$\text{9.}$ had they sold - regreted

$\text{10.}$ didn't eat - had come

$\text{11.}$ told - had never met

$\text{12.}$ did - had gone

$\text{13.}$ had begun - left

$\text{14.}$ had been - started

$\text{15.}$ left - had bought - needed

$\text{16.}$ had burnt - arrived

$\text{17.}$ did - was

$\text{18.}$ had already heard - told

$\text{19.}$ had lived - came

$\text{20.}$ didn't talk - arrived - had already left 

1. left - arrived 

2. wondered - would left 

3. didn't leave - had finished

4. entered - began

5. asked - didn't do

6. sent - realized - sent

7. gone - had

8. was - expectd

9. they sold - regreted

10. didn't eat - had come

11. told - had never met

12. did - had gone

13. begun - left

14. been - started

15. left - had bought - needed

16. burnt - arrived

17. did - was

18. heard - told

19. had lived - came

20. didn't talk - arrived - left 

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