There are other ways to use "sometimes" - adverb of frequency.

- Sometimes the students play soccer in the afternoon.

- The students sometimes play soccer in the afternoon.

- The students play soccer in the after noon sometimes.

https://llv.edu.vn/vi/phan-biet-some-time-sometime-sometimes/

Sorry. I made a mistake. It should be:

" It was not until .... that...."

** Please see the above post .

Correction:

#24 - reused

19. The talk was both (inform) … informative….and entertaining.
20. He’s (wonder) … wonderfully……fit for his age.
21. Like beverage cans, these __ products_ can be recycled.
(produce)
22. Please __ inform __all of your club members about the change in
schedule. (information)
23. She shows people how to ___protect__ the environment.
(protective)
24. Milk bottles can be __used_____ after being cleaned. (use)
25. (Prevent) …Prevention….also plays central role in traditional
medicine.
26. Findings suggest that while television is more (inform)
…… informative …than the press, it is less persuasive.
27. It can be (use) …used…to write a short summary of your
argument first.
28. The hotel is (wonder) … wonderfully …comfortable.
29. They are famous Hollywood screenwriters, actors and (produce) … producers …