The potato, _______________ the most-consumed vegetable in North America, is one of the main ingredients in fast food.

Select one:

a.

where is

b.

which is

c.

it is

d.

that is

 

These days, families spend very little time eating food together. They often share a meal at fast-food restaurants like McDonald's, ____________ only about eleven minutes.

Select one:

a.

where the average meal lasts

b.

which the average meal lasts

c.

in where the average meal lasts

d.

where the average meal is last

The answers are: 

1. b. which is

2. a. where the average meal lasts

Step-by-step explanation

That is used when the sentence does not make sense after removing the clause that follows the word that while which is used when the sentence does not change its meaning even after the close that follows the word which is removed. In our case, even if we remove the clause after the word, the sentence will still make sense since the clause is not connected to it being the main ingredient in fast food.

Where is used when we have put our focus on a place. In this case where is used and we do not put in before the word where. Also, option (d) is wrong because it changes the meaning of the sentence and it does not fit the sentence that we are trying to fill.

Source: 

1. Funk & Wagnalls Company. (1953). Standard handbook of prepositions, conjunctions, relative pronouns, and adverbs. New York: Funk & Wagnalls.
2. Fernald, J. C. (1904). Connectives of English speech: The correct usage of prepositions, conjunctions, relative pronouns and adverbs explained and illustrated. New York: Funk & Wagnalls Co.