The simple past tense of "do" is "did".
Example: When I was a child, I did not like to read books.
I did You did
He did She did
We did
You did
They did
did
Did
"They were doing an experiment" is past tense.
are is for present tense for example, what are you doing and were is past tense what were you doing
The simple past tense is did. The past participle is done.
The past tense of do is did. "We did a lot of work today. "The future tense of do is:will do - I will do the washing tonight.be + going to do - I am going to do my homework tomorrow night.be + doing - I am doing my homework later.
Did is the simple past tense. The past participle is done. Instead of saying "I am doing this" you would say "I did this". The present perfect tense is "I have done this."
Past tense: The cat chased the mouse. Present tense: The cat is chasing the mouse.
The past participle is done. The simple past tense is did. The present participle is doing.
The verb in the sentence is 'are doing,' so the past perfect tense would be 'have done.'
The past tense of "I think you are doing well" would be "I thought you were doing well."
Did is past Do is present Doing is future.
The past tense of "be" is "was/were." The present tense of "be" is "am/is/are."
The phrase "what did you doing" makes no sense grammatically; it should be "What did you do?" which is a question about the past. If it were about the present it would be "What are you doing?" and if it was about the future it would be "What are you going to do?".