Problem: Hokkien:

The existence of literary and colloquial readings (文白異讀), called tha̍k-im (讀音), is a prominent feature of some Hokkien dialects and indeed in many Sinitic varieties in the south. The bulk of literary readings (文讀, bûn-tha̍k), based on pronunciations of the vernacular during the Tang Dynasty, are mainly used in formal phrases and written language (e.g. philosophical concepts, surnames, and some place names), while the colloquial (or vernacular) ones (白讀, pe̍h-tha̍k) are basically used in spoken language and vulgar phrases. Literary readings are more similar to the pronunciations of the Tang standard of Middle Chinese than their colloquial equivalents.

colloquial reading are usually used where?
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A: spoken language and vulgar phrases


Problem: Railway electrification system:

DC commutating electric motors, if fitted with laminated pole pieces, become universal motors because they can also operate on AC; reversing the current in both stator and rotor does not reverse the motor. But the now-standard AC distribution frequencies of 50 and 60 Hz caused difficulties with inductive reactance and eddy current losses. Many railways chose low AC frequencies to overcome these problems. They must be converted from utility power by motor-generators or static inverters at the feeding substations or generated at dedicated traction powerstations.

Reversing the current in both stator and rotor also reverses what?
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A: unanswerable


Problem: Kievan Rus%27:

As the 10th century progressed, the Khazars were no longer able to command tribute from the Volga Bulgars, and their relationship with the Byzantines deteriorated, as Byzantium increasingly allied with the Pechenegs against them. The Pechenegs were thus secure to raid the lands of the Khazars from their base between the Volga and Don rivers, allowing them to expand to the west. Rus' relations with the Pechenegs were complex, as the groups alternately formed alliances with and against one another. The Pechenegs were nomads roaming the steppe raising livestock which they traded with the Rus' for agricultural goods and other products. The lucrative Rus' trade with the Byzantine Empire had to pass through Pecheneg-controlled territory, so the need for generally peaceful relations was essential. Nevertheless, while the Primary Chronicle reports the Pechenegs entering Rus' territory in 915 and then making peace, they were waging war with one another again in 920. Pechenegs are reported assisting the Rus' in later campaigns against the Byzantines, yet allied with the Byzantines against the Rus' at other times.

Whose relationship with Khazars improved?
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A: unanswerable


Problem: Greeks:

The evolution of Proto-Greek should be considered within the context of an early Paleo-Balkan sprachbund that makes it difficult to delineate exact boundaries between individual languages. The characteristically Greek representation of word-initial laryngeals by prothetic vowels is shared, for one, by the Armenian language, which also seems to share some other phonological and morphological peculiarities of Greek; this has led some linguists to propose a hypothetical closer relationship between Greek and Armenian, although evidence remains scant.

What other things do the two languages not seem to have in common ?
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A:
unanswerable