1.America (discover) .................................... by Christopher Columbus.
2.Sydney Opera House in Australia (finish) .................................. in 1973.
3. The Great Wall in China (build) ................................................ many centuries ago.
1.America (discover) .................was discovered................... by Christopher Columbus.
2.Sydney Opera House in Australia (finish) ...............was finished................... in 1973.
3. The Great Wall in China (build) .....................was built........................... many centuries ago.