Ex3. Give the correct form of the verbs in the brackets
1. By the time the conference ended, the keynote (chính) speaker (deliver)
______________ her presentation for nearly two hours.
2. By this time next year, they (renovate- trùng tu) ______________ the historical
museum for over a decade.
3. After the researchers (conduct) ______________ several experiments, they published
their findings in a scientific journal.
4. At this time tomorrow, the scientists (discuss) ______________ the potential impact
of climate change at the international summit.
5. If it had been for the Covid-19, our company (launch) _________________________
three new products in the market this year.