1- The president (won- he won- yesterday- fortunately) the election by a landslide.
2- When (the doctor attended- did the doctor attended- did the doctor attend- the doctor will attend)?
3- The North Pole (it has/ is having/ which is having/has) a latitude of 90 degrees north.
4- The city of Beverly Hills is surrounded on (its sides/the sides are/it is the side of/all sides by) the city of Los Angeles.
5- (The/ The fastest/ The fastest dog/ The fastest dog, the) greyhound, can achieve speeds up to thirty-six miles per hour.
6- Marmots spend their times foraging among meadow plants and flowers or (gets suns/ sunning/ the sun/ the sunny) on rocket cliffs.
7- The greenhouse effect occurs (when does the Earth’s atmosphere trap/ does the Earth’s atmosphere trap/when the Earth’s atmosphere traps/the Earth’s atmosphere traps) heat radiated from the Sun.
8- The Rose Bowl, (takes/ it takes/ which takes/took) place on New Year’s Day, is the oldest postseason collegiate football game in the United States.
9- Experiments (using gene therapy/ use gene therapy/ they use/ gene therapy uses)represent a giant step into medicine of the future.
10- (While some types of coral reefs/ some types of coral reefs/There are many types of coral reefs/Coral reefs) off Hawaiian coastline are living, others are dead.
11- Some economists now suggest that home equity loans are merely a new trap to push consumers beyond (they can afford/they can afforest it/what is affordable/able to afford)
12- People who reverse the letters of words (when trying / if they tried/when tried/if he tries) to read suffer from dyslexia.
13- Rubber (is produced/producing/that produces/produced) from vulcanized silicones with a high molecular weight is difficult to distinguish from natural rubber.
14- (The Moon is/ That the Moon/When the Moon/The Moon) appears considerably larger at the horizon than it does overhead is merely an optical illusion.
15- According to the World Health Organisation, (were/they were/there were/were they) any of the six most dangerous diseases to break out, it could be cause for quarantine.
16- The A four string B on a violin are C tuned D.
17- The research A for the B book ‘Roots’ taking C Alex Haley twelve years D
18- On the floor A of the Pacific Ocean is B hundreds of flat-topped C mountains more than D a mile beneath sea level.
19- Killer whales tend A to wander B in family clusters, play, and resting C together D.
20- The community A of Bethesda, Maryland, was previous B known C as D Darcy’s Store.