3. Fill in the gaps with was, were, wasn't or weren't. 1. We... together at the zoo yesterday. 2. It ... cloudy when we went to the park. 3. Were you in the chemist's? - No, I ... . 4. Joe and Mark ... at the school. I didn't see them there.

Решение:

Мы используем was/wasn't для единственного числа (I, he, she, it) и were/weren't для множественного числа (we, you, they). Также учитываем контекст предложения (утверждение или отрицание).

1. We were together at the zoo yesterday. (We – множественное число, утверждение).
2. It was cloudy when we went to the park. (It – единственное число, утверждение).
3. Were you in the chemist's? - No, I wasn't. (Вопрос был с 'you', но ответ от первого лица 'I', поэтому используем wasn't).
4. Joe and Mark weren't at the school. I didn't see them there. (Joe and Mark – два человека, множественное число. Так как мы их не видели, используем отрицание weren't).

Ответ: 1. were, 2. was, 3. wasn't, 4. weren't