In Chinese we don’t have forms of singular and plural for nouns. As a result, unless there is an indication to need to express the forms of the number, one shall not worry about to make a sentence implying the singular or plural forms of the object.

For example, in Chinese it’s perfectly ok to say “这是猫”, whereas “这是只猫”, or “这些是猫” are also correct. Same rule won’t be able to apply to an English phrase. In English the grammar requires the forms of singular and plural. It’s forced to indicate the quantity state under every situation. In Chinese grammar quantity forms don’t exist; since it’s not a feature of our language we do not give a great consideration to quantity unless the content to the sentence to specifically indicate it.