When is proper to use is in grammar?

Answer 1

The word "is" can be used to describe permanent traits of a person, place, or thing as well as temporary states (such as locations both in terms of space and in time). The word "is" should be used for only one person or thing - never with plurals. You could say, for example, "He is happy" or "Carlos is happy" but you couldn't say "Carlos and Maria is happy" instead you should say "Carlos and Maria are happy."

Do not use "is" with the pronoun "I" or the pronoun "you". Do not use is to refer to the past. Sometimes is can refer to the future (e.g., The meeting is tomorrow.). Is can also be used as part of a continuous action: "Maria is dancing" to refer to an action in progress at a certain point in time or to an action scheduled for a specific time in the future (e.g., John is arriving in Peru tomorrow.). Some verbs are not used in a continuous fashion even though they refer to the present. One example is the verb "need" - we say "He needs to go to the bathroom" not "He is needing" as need is not an action verb that progresses like, for example, cooking something that has a beginning, middle, end, and progress between the stages.

Answer 2

"Is" is used in grammar when referring to singular subjects in the present tense, while "are" is used for plural subjects. For example, "She is going to the store" vs. "They are going to the store".