What is the difference between "aspire" and "desire"? When should I use them?Would you mind to give me some examples so I can understand more?

Million Thanks
Aspire is attempting to achieve a specific (usually lofty and long term) goal, whereas desire is wishing/hoping/wanting something.

For example, in describing someone's ambition:

"He aspires to be the next Prime Minister"

Yes, you could also rewrite it to:

"He desires to be the next Prime Minister"

but the subtle difference is the first (aspire) is telling about his (long term) ambition, whereas the second (desire) is a weaker statement/description of his ambition.

But, if he simply wants an ice-cream (because it's a hot day), it is better to write:

"He desires an ice-cream" rather than "He aspires to have an ice-cream"

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Can I say : I aspire to be your husband/wife? This is a kind of lofty aim,right?

Are these correct?

I desire to ride that highest roller coaster in the world.

I aspire to be the first among all in this academic year/in this semester. (Though this is not long-term, but i think it is grand enough to be lofty.)
Yes, you could write "I aspire to be your husband/wife?" but I must say it is rather unusual in this case to use "aspire". Perhaps the following will give you an idea when "aspire" is more suited:

"I aspire to interview the Dalai Lama one day"
"I aspire to climb to the top of Everest"
"I aspire to the best heart surgeon in this country"
"I aspire to be Top 5 in my class"
"The Chinese urban planners aspire Dongtan to be the best eco-city in the world"
"She aspires to reach the finals in American Idol"

Well described,absolute clarity,to the point and precise.Much appreciated and many thanks.
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