11. wasn't driving/happened

12. was you watching/phoned

13. broke. was doing/slipped

14. saw. was wearing

15. was reading/ was watching/ was making

16. saw. was sitting/ was reading. called/didn't hear

17. didn't shave/ didn't have

18. invited/ decided

19. came/ wasn't

20. was breaking/ joined

21. phần sau bị khuất nên mik ko làm nha.

Chúc bạn học tốt!

$\text{11.}$ was driving/ happened 

$\text{→}$ When/ While + QKD/ QKTD, QKD/ QKTD: hợp nghĩa

$\text{12.}$ Was you watching/ phoned

$\text{13.}$ broke/ was doing/ slipt

$\text{→}$ Last night chia QKD

$\text{14.}$ saw/ was wearing

$\text{→}$ hợp nghĩa

$\text{15.}$ was reading/ were watching/ was making

$\text{16.}$ saw/ was sitting/ reading/ called/ didn't hear

$\text{→}$ hợp nghĩa

$\text{17.}$ didn't shave/ didn't have

$\text{→}$ hợp nghĩa

$\text{18.}$ invited/ decided

$\text{→}$ Last week chia QKD

$\text{19.}$ came/ wasn't

$\text{→}$ Yesterday chia QKD

$\text{20.}$ broke/ was joining

$\text{21.}$ drove/ happened/ crashed

$\text{→}$ hợp nghĩa