I know "do & did" can be used as an auxiliary verb for emphasis as in
ex1. I did do my homework.
ex2. I do love you.
While "should" can also be used as an auxiliary verb, it can only be used for emphasis in the past conditional, as in
ex1. I should have done my homework.
ex2. I should have loved you more.
However, "should" cannot be used as an auxiliary verb in the present/future conditional, as in
ex1. I should do my homework.
Is this understanding of the usage of "should" correct?
I should have done my homework / I should have loved you more. "Should" is an auxiliary verb, a modal auxiliary to be precise, though unlike the non-modal auxiliary "do" it is not used to emphasise positive or negative polarity. Note that your "should" examples are not necessarily conditionals (more context is needed).
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I should have done my homework / I should have loved you more.
"Should" is an auxiliary verb, a modal auxiliary to be precise, though unlike the non-modal auxiliary "do" it is not used to emphasise positive or negative polarity.
Note that your "should" examples are not necessarily conditionals (more context is needed). In your examples, should" is used w
grammarsuckerI know "do & did" can be used as an auxiliary verb for emphasis as in
ex1. I did do my homework.
ex2. I do love you.
Nine times out of ten this "emphasis" consists of denying a negative claim.
— You didn't do your homework, did you?
— Yes, I did. I did do my homework.
— I can see now that you don't love