Boundaries
Generations of mystery and horror ______blank have been influenced by the dark, gothic stories of celebrated American author Edgar Allan Poe (1809–1849).
A. writers
B. writers,
C. writers—
D. writers;
A. writers
Subject followed by verb.
Researchers Amit Kumar and Nicholas Epley investigated how ______blank In a series of experiments conducted in 2022, they found that people performing small acts of kindness underestimated the positive effect their actions had on others.
A. do people perceive acts of kindness.
B. do people perceive acts of kindness?
C. people perceive acts of kindness?
D. people perceive acts of kindness.
D. people perceive acts of kindness
The radiation that ______blank during the decay of radioactive atomic nuclei is known as gamma radiation.
A. occurs
B. have occurred
C. occur
D. are occurring
A. occurs
In recent years, economists around the world have created new tools that quantify the overall well-being of a country’s citizens. Economists in India, for example, use an Ease of Living Index. This tool ______blank economic potential, sustainability, and citizens’ quality of life.
A. measures
B. had measured
C. would have measured
D. will have been measuring
A. measures
The Mission 66 initiative, which was approved by Congress in 1956, represented a major investment in the infrastructure of overburdened national ______blank it prioritized physical improvements to the parks’ roads, utilities, employee housing, and visitor facilities while also establishing educational programming for the public.
A. parks and
B. parks
C. parks;
D. parks,
C. parks;
There are two main clauses in this sentence.
A study led by scientist Rebecca Kirby at the University of Wisconsin–Madison found that black bears that eat human food before hibernation have increased levels of a rare carbon isotope, ______blank due to the higher 13C levels in corn and cane sugar. Bears with these elevated levels were also found to have much shorter hibernation periods on average.
A. carbon-13, (13C)
B. carbon-13 (13C)
C. carbon-13, (13C),
D. carbon-13 (13C),
D. carbon-13 (13C),
French philosopher René Descartes doubted whether he could prove his own existence. Eventually, he found proof in his famous phrase “I think, therefore I am.” The ______blank complexity: only those who exist would be able to ponder their existence.
A. phrases’ simplicity masks its
B. phrases simplicity masks their
C. phrase’s simplicity masks their
D. phrase’s simplicity masks its
D. phrase’s simplicity masks its
Bonnie Buratti of NASA’s Jet Propulsion Laboratory ______blank data about Saturn’s rings collected by the Cassini spacecraft when she made an interesting discovery: the tiny moons embedded between and within Saturn’s rings are shaped by the buildup of ring material on the moons’ surfaces.
A. studies
B. has been studying
C. will study
D. was studying
D. was studying
A recent study tracked the number of bee species present in twenty-seven New York apple orchards over a ten-year period. ______blank found that when wild growth near an orchard was cleared, the number of different bee species visiting the orchard decreased.
A. Entomologist Heather Grab:
B. Entomologist, Heather Grab,
C. Entomologist Heather Grab
D. Entomologist Heather Grab,
C. Entomologist Heather Grab
The Limón technique, developed by Mexican-born dancer and choreographer Jose Limón, is known for its emphasis on breath control and its interplay of weight and ______blank dancers may explore, for example, the moment of mid-air suspension at the top of a jump.
A. weightlessness
B. weightlessness which
C. weightlessness,
D. weightlessness;
D. weightlessness;
Two main clauses.
American abstract artist Richard ______blank his installations to make passersby keenly aware of how one’s movements are affected by the physical features of one’s environment, assembles large-scale steel plates into sculptures that dominate the outdoor spaces they occupy.
A. Serra is intending
B. Serra, intends
C. Serra, intending
D. Serra intends
C. Serra, intending
In a recent analysis of lyrical trends in 350,000 songs, researchers cite increases in certain measures, such as the ratio of choruses to verses, as evidence music lyrics are becoming more repetitive. For instance, from 1970 to 2020, ______blank chorus-to-verse ratios trended similarly, with each genre’s data indicating that relative to the number of unique verses, the number of repeated choruses in songs increased.
A. rocks and raps
B. rock’s and rap’s
C. rocks and rap’s
D. rock and rap’s
B. rock’s and rap’s