Do/Does

[Vivienne]

How can I explain why this is incorrect:

"What colour eyes does he/she has?"

and

"What does your father is do?"

Thank you

[Joe]

[Question word/phrase] + AUXILIARY + SUBJECT + MAIN VERB (bare infinitive) + ?

In 1 "has" is not the bare infinitive. Should be:
"What colour eyes does he/she have?"

In 2 "is do" is two verbs. Should be:
"What does your father do?"

See Question Word Questions

[jirkux]

The auxiliary (do, does, did) is kind of an "operator". It doesn't have any meaning it just forms the question and it likes to take on all the "grammar". It takes the third person -s so you don't need it any more:

He likes music.

What does he like?
(we don't need the -s any more with the verb like here, because it's included in the operator already).

[doomer]

In questions, "does" can only only take a 3rd person noun (singular) + a base verb:
Does + 3S + V.

No other verb forms are allowed (past, etc). Test for yourself.
The only base verb that isn't allowed is "be". (Does he be = incorrect)
There are no exceptions to this rule.

For other 'person' nouns, use "do", which also can only take a base verb:
Do + (1,2,3P) + V.

Again, there are no exceptions to this rule. Test for yourself.

Do/does are only used for "present tense" questions which have a verb as their main "target". All other "targets" require a "be verb". (This can also be laid-out formulaically.)

Personally, I don't teach most of the traditional grammatical terms or explanations, which are more suited for NES grammarians. I find they only add an unnecessary layer of complexity that just confuses EFL students. (Then many end up hating grammar.)

Like other rules (eg, class management), grammar should be simplified whenever possible (without sacrificing accuracy) into visually minimalist forms that are easier for students to remember, apply, & self-correct.

If an error is made, I signal it and ask, "What's the rule?" And they say, "After do or does, you can only put a base verb." After a few months, the error rate is drastically reduced.

[Lola212]

I like the signal idea. That will really stick with the students. Also, as you put it, "After a few months, the error rate is drastically reduced". Great Stuff!

[Mrdaudiqbal]

In questions, "does" can only only take a 3rd person noun (singular) + a base verb:
Does + 3S + V.

No other verb forms are allowed (past, etc). Test for yourself.
The only base verb that isn't allowed is "be". (Does he be = incorrect)
There are no exceptions to this rule.

For other 'person' nouns, use "do", which also can only take a base verb:
Do + (1,2,3P) + V.

Again, there are no exceptions to this rule. Test for yourself.

Do/does are only used for "present tense" questions which have a verb as their main "target". All other "targets" require a "be verb". (This can also be laid-out formulaically.)

Personally, I don't teach most of the traditional grammatical terms or explanations, which are more suited for NES grammarians. I find they only add an unnecessary layer of complexity that just confuses EFL students. (Then many end up hating grammar.)

Like other rules (eg, class management), grammar should be simplified whenever possible (without sacrificing accuracy) into visually minimalist forms that are easier for students to remember, apply, & self-correct.

If an error is made, I signal it and ask, "What's the rule?" And they say, "After do or does, you can only put a base verb." After a few months, the error rate is drastically reduced.

hmmm very helpul and informative material