I had a hard time _____ his house.
  A) find
  B) to find
  C) found
  D) finding

  You will pass the exam _____ you get over 50% in each section.
  A) provided
  B) unless
  C) so
  D) otherwise

  Let's not waste time _____ about this.
  A) argue
  B) arguing
  C) having argued
  D) to have argued

  Planners who want to eliminate heavy traffic have suggested that
  people_____ to share their cars.
  A) asking
  B) asked
  C) have been asked
  D) be asked

  The boy _____ a blue jacket is an excellent tennis player.
  A) worn
  B) wearing
  C) to be worn
  D) wears

  _____ them, she didn't answer.
  A) Not having heard
  B) Not having been heard
  C) Not to have heard
  D) Not being heard

  I would have _____ all night if I could but we all had to leave early because Carmen didn't feel good.
   A) sing
   B) sung
   C) sang
   D) singed

  All relevant documents , duly _____ , should _____ in at the secretary's
  office one week before the start of term.
  A) completed / hand
  B) completing / handed
  C) completed / be handed
  D) to be completed / hand

  The developing countries that are producers of primary products
  are those that have minerals and foodstuffs _____ by the_____
  countries.
  A) needing / industrialized
  B) needed / to industrialize
  C) needed / industrialized
  D) be needed / industrializing

  I would rather _____ out last night.
  A) not to have gone
  B) not go
  C) not to go
  D) not have gone