Your answer is detailed below:
IS is the singular present form of the verb ‘to be’ – it is used with nouns and pronouns.
For example:
- She is twenty years old
- He is from Australia
- It is very heavy
- Nadia is my friend
- Life is beautiful
- That is heavy
- This is fun
If you want to use this in a plural form you would use ARE with a suitable noun or pronoun .e.g.
- They are very young
- We are from England
- Those are heavy
- Dreams are inexplicable
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WAS is the singular past form of the verb ‘to be’ – it is used with nouns and pronouns.
For example:
- She was in my class
- He was always happy
- This was his house
- Daniel was late
- Their house was messy
- It was his fault
If you want to use this in a plural form, you would use WERE with a suitable noun or pronoun .i.e.
- They were in my class
- John and Sarah were always happy
- These were his clothes
- Their bedrooms were always messy
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THAT is a demonstrative pronoun, which applies to the above. You use it to ‘point’ at nouns, so to speak. Here are some examples:
- That is a big house
- That is mine
- That is not heavy
- That was tasty
- That was a sad movie
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THE is an article, it is always followed by a noun, I have listed some examples below:
- The house
- The bedroom
- The cat
- The table
Here are some sentences that use all the words related to your question:
- This school is fantastic
- I was late for school
- She is my best friend
- This is my mother
- That dress is beautiful
- That party was great fun
- The principal was unwell
I hope this answers your question!
