모르는것 여기다가 올려두 된다구 아는분이 그래서 처음으로 아니 2번째로
올려봅니다. 감사합니다.
PG106
12. since the end of WW2, American’s involvement in world affairs grew.
Since 들어가면 무조건 have/has past participle 인가요?
13. Pigeon racing has been once a popular sport in the U.S.
Had로 고쳐야될것도같은데.. had been인가..
16. For the last twenty years, NASA scientists had been working on improvements in the space shuttle.
has been working 인가요? 잘 이해가안되요 ㅠ ㅠ