The words 'conversion' and 'treasure' can be both countable 可数名词 and uncountable 不可数名词 depending on the context.
In the programme Yang Li provides examples to show you how these two words are commonly used in everyday English.
She also looks at the verb form of these two words:
Conversion (noun) - to convert (verb)
Treasure (noun) - to treasure (verb)
"I have a question about plural nouns in English. Sentence One: "When I am abroad I need a calculator to work out my currency conversions". Sentence Two: "They dreamed of finding hidden treasure in the ruins of the ship". 'Conversion' in the first sentence and 'treasure' in the second one are both mass nouns, but why does 'conversion' end with 's' and why does 'treasure' not? Thanks in advance."
《 Conversion and treasure 两词用法》出自：天天学英语