Complete each sentence with the correct form of the word given in brackets. Then press "Check" to mark your answers.
  1. Following the end of slavery, American blacks faced tremendous (obstacle) in their attempt to join the mainstream of society.
  2. In March of 1997, the government of Albania (resign) after the deadliest violence in two months of angry unrest.
  3. In 1977, the Voyager spacecraft photographed the first (image) of Jupiter, Saturn, Uranus, and Neptune.
  4. Teaching students to have realistic expectations is an important part of second language (instruct).
  5. During the Chinese New Year, gifts bring special (symbol) wishes for the coming year.
  6. Successful (alternate) to testing drugs on animals include test tube studies on human tissue cultures, statistics, and computer models.
  7. It has been (calculate) that there may be millions of planets in other parts of the universe capable of supporting some kind of life.
  8. Gillian is a little weak because she's just got over the flu, so she can't do anything too (tax) right now.
  9. She is (determine) to quit her job and travel around Europe for a year.
  10. (honest) honey, I'm sorry. I promise it will never happen again.