interest
In Spanish, 'interés' is used much as it is in English. It can refer both to a sense of curiosity or concern about something ('Tengo interés en este tema' - 'I have interest in this topic'), as well as the money paid regularly at a particular rate for the use of money lent, or for delaying the repayment of a debt ('El banco cobra un 3% de interés' - 'The bank charges 3% interest').
I have no interest in politics.
En este caso, el hablante está declarando la falta de interés en un tema específico, en este caso, 'la política' (politics).
I have a great interest in learning Spanish.
The phrase 'Tengo un gran interés' means 'I have a great interest'. 'En' is used before the activity (in this case, 'aprender español') which is the object of interest.
My main interest is music.
In Spanish, 'interés' is used similarly like in English to indicate something that one likes or pays attention to. In this case, 'la música' (music) is the main interest.
What is your interest in this project?
This is a question that asks about a person's interest in a certain subject or project. '¿Cuál es tu interés?' means 'What is your interest?'
He had a great interest in sports since he was a child.
In this instance, the phrase 'tuvo un gran interés' conveys past interest that the person 'en los deportes' (in sports) had since childhood.
Our interest is to improve the community.
In this sentence, 'Nuestro interés' refers to the collective interest of a group of people. The verb 'es' serves to equate this interest with the action of 'mejorar la comunidad' (improving the community).
You have an obvious interest in this area.
This sentence is a commentary on the receiver's obvious interest ('interés obvio') in a certain area or field.
My interest in science was awakened.
This is a reflective sentence where the receiver's interest ('mi interés') 'fue despertado' (was awakened). 'Por la ciencia' indicates the field where the interest lies.
What are your interests?
This is a common question to ask about a person's hobbies or areas of interest. Note that 'intereses' is plural in this context.
The interests of the students are varied.
This sentence talks about 'los intereses' (the interests) of a group of people (in this case, 'los estudiantes' or the students) being varied ('son variados').