Каковы особенности строения, жизнедеятельности двустворчатых моллюсков? В чём их сходство с брюхоногими моллюсками?

1. There are a lot of cows in the field.
2. The weather was rainy last summer.
3. Were you in the country last Sunday?
4. My mum's eyes are blue.
5. Where were they a month ago?
6. We weren't in the desert last year.