. Thousands of people (save) __________________because scientists had warned them about the volcanic eruption.
24. Tet is a festival which (occur) _________in late January or early February.
25. Recently, there (be) __________________a lot of changes in our city.
26. All buildings in Sweden (heat) __________________by solar energy in 2015.
27. If the weather were better today, we (go) __________________on a picnic.
