Help me, please
Выберите. Choose the correct form.
1. The children( CLEANED/HAVE BEEN CLEANING) the playground yesterday.2. She( HAS STUDIED/HAS BEEN STUDYING) all day. 3. I( WORK/ HAVE BEEN WORKING) without a break since 8 o’clock. 4. I (HAVE BEEN WALKING/WALKED) to the park last week.