fish is/are

[michaelfung]

Are both sentences correct?
1.Fish is cold-blooded.
2.Fish are cold-blooded.

[Steven D]

Are both sentences correct?
1.Fish is cold-blooded.
2.Fish are cold-blooded.

Fish is good for your health. - food - uncountable noun

People eat lots of different types of fish. - There are different types of fish that people eat. There is more than one type. It's possible to count them.

Fish are cold-blooded. - living creatures - countable

fish - singular and plural

It's possible to use "fishes" as the plural form. However, I usually use "fish" for the plural form, and I would say most others do as well.

[michaelfung]

I need a clearer answer.Are both sentences correct? If both sentences are correct, is there any difference in meaning?

[Casiopea]

In addition to XMode's excellent post,

1. Fish is cold-blooded.
=> If it means, fishmeat is cold-blooded, then it's grammatical, but semantically awkward because living things are cold-blooded, not meat.

=> If it means, a fish, then it's fine semantically, but incorrect grammatically. The reason being, the verb is singular, so the subject 'fish' must be singular, too, and since fish can be counted, 'fish' a singular noun, which means a determiner is required; e.g., The fish (I'm holding in my hand) is cold-blooded.

2. Fish are cold-blooded.
=> In this example, the verb is plural 'are', which means its subject is plural, too. 'Fish' is the plural of 'fish'; same form, different meaning. How do speakers know? They wait for the verb. If the verb is singular, then 'Fish' is deemed singular, one fish, and if 'Fish' is plural, then it's deemed plural, more than one fish. In 2., though, the meaning expressed is, all fish are cold-blooded. That reading is expressed by the verb BE, notably 'is'. The verb BE is often used to express a general fact: It's a general statement of fact that all fish are cold-blooded. Also,
Houses are expensive. (In general, houses are expensive)

Hope that helps.

Note, the plural noun 'fishes' has recently made its way into the English language. It's new and mostly used by people who deal in fisheries or biological sciences. It refers to "species" of fish.