Put the verbs in brackets into the correct form

Put the verbs in brackets into the correct form.( 1.5 points)
1. Radio waves(discover)……………………………. by Heinrich Hertz
2. We plan(have) ………………a picnic this Sunday. Would you like to join us?
3. They didn’t mind(work)……………………… late to complete the task.
4. She(lie) …………on the beautiful beaches in California this time next month.
5. Ana (not study)……….. at school at 8 o’clock last Monday because she was ill.
6.The kangaroo (become) _____________ a symbol of Australia since 1973.
7. If there were more trees in this area, the air ( be) _____________ fresher.
8.The earthquake occurred at midday when they (have) _____________lunch.