3. be trace -> be traced (bị động)
4. be widening -> be widened (bị động)
5. invented -> was invented (bị động)
6. allow -> allowed (bị động)
7. gift -> lift (give somebody a lift: cho đi nhờ xe)/ is repairing -> is being repaired
8. has said -> has been said (bị động)
9. to take -> to be taken/ quality -> quantities (bị động)
10. cutting -> cut (have + something + P2)