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Why does the verb "haber" sometimes not match the person and number of the subject in a sentence?

The main uses of the verb "haber" include its use as an auxilliary verb (ha comido) and as part of a verbal periphrasis (he de soportar), in this case, the person (first, second or third person) an...
HZ
Answered by Hui Z. • Spanish tutor
4123 Views

How can crude oil be used as a source of hydrocarbons?

Crude oil is a natural mixture of many different hydrocarbons. These hydrocarbons can be separated using a process known as fractional distillation .The crude oil is heated in a fractioning column allowing t...
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Answered by Thomas W. • Chemistry tutor
5568 Views

What are some good Spanish idioms to include in my research essay?

Although it depends what your research essay is on (i.e. you can't use the same idioms if you are writing an essay on a novel character and on a historical event), there are a few good ones that can be used ...
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Answered by Vittoria S. • Spanish tutor
24266 Views

How can I memorise criticisms if I don't know the exam question?

At first, this seems like something hard to do. However, when you think about it, you realise it's just the same as knowing which quotes to memorise in a closed book exam. The easiest way to go about doing t...
VS
5038 Views

What are the three isolation barriers by which speciation can occur?

Speciation is a complex topic, and indeed what defines a species is still debated today. However, one factor is key to the process of speciation; gene flow. Gene flow between populations of a species ensures...
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Answered by John M. • Biology tutor
21535 Views