It is believed that military strategists in the medieval ages used manned kites surveying enemy troops, so anticipating techniques of
modern aerial surveillance.
The sentence means that it is believed that in the medieval ages, military strategists used manned kite. They did so to survey enemy troops. This technique of the past led to the modern aerial surveillance.
1. The verb-ing modifier “surveying” is modifying kites because it is not preceded by a comma. However, from the meaning of the sentence, the purpose of using manned kites was to survey the enemy troops. Hence, we must to+verb to denote the purpose.
2. Another verb-ing modifier “anticipating” is modifying the preceding clause “strategists used manned kites”. However, placemen of “so” before this modifier denotes that anticipation was a conscious effort on the part of the strategists. This is certainly not the intended meaning of the sentence. So this part has to be changed.POE:(A)
used manned kites surveying enemy troops, so anticipating techniques of. Incorrect
for reasons stated above.(B)
were using manned kites to survey enemy troops anticipating techniques of: Incorrect.
Firstly, this sentence is providing general information about the strategists and hence must be written in the simple past tense. Use of past continuous is incorrect. Secondly, verb-ing modifier “anticipating” is now modifying “enemy troops”, suggesting that enemy troops anticipated the modern aerial surveillance. This is absolutely illogical.(C)
had used manned kites, surveyed enemy troops, and anticipated techniques of: Incorrect.
Firstly, use of past perfect tense is not correct because it is unnecessarily establishing the sequencing here. Secondly, “surveyed” now does not denote the purpose of using the manned kites. “anticipated” again looks like a conscious action done by the strategists.(D)
used manned kites to survey enemy troops, a technique anticipating: CORRECT
. “to survey” correctly denotes the purpose now. “a technique anticipating” is modifying the entire clause. We have a noun (a technique) + noun modifier (anticipating modern aerial surveillance). Noun + noun modifiers can zoom into any aspect of the preceding clause to modify it. Here it is modifying the entire clause.(E)
using manned kites to survey enemy troops, were anticipating techniques of: Incorrect.
Firstly, verb-ing modifier “using” is illogically modifying “medieval ages”, suggesting they used manned kites. Again, this choice denotes that the strategists were consciously anticipating the modern aerial surveillance. This is not the intended meaning of the sentence.
1. Noun + noun modifiers can modify either a noun entity or the entire preceding clause.
2. When presenting general facts, we must use simple tense (present/past).
3. Be wary of changes in the sentence that distorts the original meaning.
Hope this helps.
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