Решение:
Заполняем пропуски, используя правильную форму глаголов 'to be' (was/were) или 'could/couldn't' в прошедшем времени.
- Yesterday was my birthday, and last night my friends and I went at a BTS concert.
- It was great, but there were too many people (not) to see the band very well.
- Fortunately, the sound was good so we could hear all the words.
- It was the best concert, but it wasn't still a wonderful birthday!
Ответ: 1. was; 2. went; 3. was; 4. were; 5. to see; 6. was; 7. could; 8. was; 9. wasn't