Question

schools change history. quarter 1 unit exam
19 genealogy is the study of family origins and history. genealogists ______ lists of ancestors, which they arrange in pedigree charts or other written forms.
20 genetic genealogy creates family history profiles, biological relationships ______ dna test results in combination with traditional genealogical methods. by using genealogical dna testing, genetic genealogy can determine the levels and types of biological relationships between or among individuals.
21 this branch of genetics became popular in recent years, as costs ______ drastically reduced and genealogical studies using molecular techniques became accessible to the general public.
luis felipe guerra is intrepid deputy operations manager in guatemala, but he is also maya, and a tour guide. as a child, he struggled to come to terms with his indigenous heritage. 22 ______ by discovering more about his history, and sharing it with travelers, he has learned to take pride in it. now he wants to help young guatemalans do the same.
23 in high school, ______ geared towards careers in tourism. luis learned about the equinox and how the maya planned their agriculture by following astronomical events, by learning the rhythm of the seasons. he found a passion to share the history of his people, to share thousands of years of civilization with anyone that wants to know about it.

Explanation:

1. Question 19:

• “Genealogists” is a plural subject. The verb should agree in number. “Compile” (base form for plural) is correct. “Compiles” is for singular. “Compiling” is a non - finite form (present participle) which doesn't fit the simple present tense context. “Have compiled” is present perfect, but the sentence describes a general action (arrange lists regularly), so simple present is better.

1. Question 20:

• “Between” is used for two entities, and “among” for more than two. Here, it's about relationships among multiple individuals. Also, the correct prepositional phrase structure is “by using” (indicating the means). “By, using” has an incorrect comma placement.

1. Question 21:

• “Costs” is plural. In the present perfect (implied by the context of recent years and the effect on the present - became accessible), the correct form is “have been reduced” (but since we are just looking at the verb form for the blank, considering the simple past (as the events are in the past and completed) “were” (for plural) is wrong. Wait, no - actually, “costs” is plural. In the context of “as costs... reduced”, if we consider the simple past (because the reduction happened in the past and led to the present situation of being accessible), “were” is wrong. Wait, no - “costs” is plural. The correct form is “have been reduced” (present perfect), but if we assume a simple past (maybe a typo in the options), but actually, looking at the options:
• “Are” (present tense) is wrong as the action is in the past (related to recent years and the past reduction leading to present accessibility). “Is” (singular) is wrong. “Was” (singular) is wrong. Wait, no - actually, if we consider the structure “as costs... reduced” (passive voice). The correct form for plural “costs” in simple past passive is “were reduced”. But if we consider the present perfect (more appropriate for recent years - a time period that includes the present), but the options don't have “have been”. Wait, looking at the options again. Wait, no - the sentence is “as costs... drastically reduced and genealogical studies... became accessible”. “Became” is simple past. So “costs” (plural) with simple past passive “were reduced” (but the options have (A) are (B) is (C) was (D) were. So “costs” (plural) - “were” (D) is correct (even though present perfect would be better, but given the options and the parallelism with “became” (simple past), “were” is the best fit).

1. Question 22:

• “Previously” (C) makes sense as it contrasts his past struggle (as a child) with his present situation (now taking pride). “Essentially” (A) means basically - not relevant. “Nevertheless” (B) means in spite of, but there's no contrast in that sense. “Therefore” (D) means as a result - no causal relation here.

1. Question 23:

• “Students'” (plural possessive) is correct as it's about multiple students' lessons. “Student's” (singular possessive) is wrong. “Students's” is an incorrect plural possessive form (should be “students'”).

Answer:

1. A. compile
2. B. between or among individuals by using
3. D. were
4. C. Previously,
5. C. students' lessons were