LEVEL 2

In 1990, California native and researcher Ellen Ochoa left her position as chief of the Intelligent Systems Technology Branch at a NASA research center _____ the space agency’s astronaut training program. Which choice completes the text so that it conforms to the conventions of Standard English?

• to join

• is joining

• joined

• joins

Which choice completes the text so that it conforms to the conventions of Standard English?

• have outlined

• were outlining

• outlines

• outline

If simple sugars such as ribose and glycolaldehyde _____ Earth from elsewhere and survived impact—a possibility astrophysicist Nicolle Zellner outlined in a 2020 study—the sugars could have reacted with other molecules that were already present on the planet to form the nucleotides that are the structural components of RNA and DNA. Which choice completes the text so that it conforms to the conventions of Standard English?

• reach

• had reached

• will reach

• are reaching

In order to prevent nonnative fish species from moving freely between the Mediterranean and Red Seas, marine biologist Bella Gail has proposed that a saline lock system be installed along the Suez Canal in Egypt’s Great Bitter Lakes. The lock would increase the salinity of the lakes and ______ a natural barrier of water most marine creatures would be unable to cross. Which choice completes the text so that it conforms to the conventions of Standard English?

• creates

• create

• creating

• created

Farouk El-Baz, a geologist and space scientist, _____ part of the team that selected the lunar landing sites for the Apollo program during the 1960s and 1970s. Which choice completes the text so that it conforms to the conventions of Standard English?

• are

• was

• have been

• were

In 1899, Swedish chemist Svante Arrhenius developed an equation to answer a long-standing question: why do chemical reactions speed up at higher temperatures? The Arrhenius equation, named for its creator, _____ an important concept in modern chemistry. Which choice completes the text so that it conforms to the conventions of Standard English?

• have remained

• remain

• remains

• are remaining

Bengali author Toru Dutt's A Sheaf Gleaned in French Fields (1876), a volume of English translations of French poems, _____ scholars’ understanding of the transnational and multilingual contexts in which Dutt lived and worked. Which choice completes the text so that it conforms to the conventions of Standard English?

• has enhanced

• are enhancing

• have enhanced

• enhance

Which choice completes the text so that it conforms to the conventions of Standard English?

• being

• to be

• to have been

• will be