In the process of my TESOL certification I took an English grammar class and got a really good explanation for when we use “do” in English focused on if Spanish was your first language but also how we show emphasis.

Talina’s English Help 101….When do I use do? This was thanks to notes taken in my Modern English Grammar class at MSU taken with Professor Michael Ellis.

\ (^0^) / WOOT! Go Grammar go!!!

Three types of Sentence Transformations!!

emphatic, yes/no questions, and negative
Muhahahaha!!!!
I know this may seem like overkill but I thought all the extra stuff might help you get the big picture and understand when to use “do,” which will help you with the negatives too.
Knowing about sentence transformations will help you know when to use do!

“Do you have to go pumpkin smashing tonight?”
“What do you like to do?”
“The things she does make me want to kill her!!”

There are two different “dos” in the same way there are two different verbs in Spanish for “to have,” tener y haber. Can you see the difference?
Below is grammar crap….yeah I know exciting huh?….but if you look through it I think it will you, so bear with me!

1. Linking Verbs

Emphatic, or just a regular ol’ statement…

Bob —is— an idiot.
Bob —is— the president.
Bob seems….
Bob appears...
etc…

Is links Bob to the adjective idiot, so the verb “to be” is a linking verb, also known as a copula.  Seem, appear, and become are also linking verbs.  When you want to emphasize the fact Bob is an idiot, you put emphasis on the word “is” while you’re saying it. It’s like having an accent on the word or something or a raised pitch.  The linking verbs links one idea to another, which is usually an adjective and sometimes a noun.

For a negative…

Let’s make it a negative sentence now! Yay!

Bob is NOT an idiot. (*cough*yeah right…) Emphasis is on the not.

For a yes/no question…

Is Bob an idiot?

2. Auxilary/Helping verbs
“haber” in Spanish is one.  These little guys are always helping out the verbs who just can’t seem to do stuff on their own, so they “help” out!  They are verbs before the main verb.

Emphatic…

Bob can sing like Elvis.

*Can* helps the verb *sing* and therefore is the helping verb.  “Can” is what you say a little louder to emphasize it.

Others…
The students should have been studying for the test but got wasted instead!
should, have, and been are “helping verbs” and studying is the main verb.

!!!!*some verbs like “to have” and “to be” aren’t always helping verbs.*!!!!

Other auxilary verbs are may, might, shall, should, will, would etc…

Negative…

Bob can NOT sing like Elvis.

Emphasis is on the not.

Yes/No Question…

Can Bob sing like Elvis?

3. Everything Else…

*…insert DO!  If there isn’t a linking verb or helping verb put DO which doesn’t really have an equivalent in Spanish! It isn’t the same as “hacer” when it is used this way.

Emphatic…

a.Bob ATE the moldy pizza. X P

For EMPHASIS, unlike 1.(linking verbs) and 2.(auxiliary verbs), which are made phonologically by saying one word LOUDER,  here you add a word. Since there are no “helping verbs” and no “linking verbs,”
this transforms into….

b.Bob DID EAT the moldy pizza!

When you say the say b. it’s almost like you can’t believe it! a. is more like you’re just stating a fact but b. is like you’re really trying to convince someone who doesn’t believe you.

Negative…

Bob DID NOT EAT the moldy pizza!

Yes/No Questions..

DID Bob EAT the moldy pizza?

Compare this to *Bob DID EAT the moldy pizza!*

Did I explain everything clearly? If not, PLEASE let me know since I’ll be doing this as a living after all!