[Grammar] Might or might have?

[Creamcake]

Hi experts,

I have always been told that might is the past form of may, but when I do an exercise like this:
She might be ill yesterday.

the correct answer turns out to be:
She might have been ill yesterday.

Is this because might has been too interested in the present that it abandoned the past completely?

Thank you!

 

[MikeNewYork]

"The Corbyn supporter said that Corbyn might leadership win the election." :cross:

In the next set, change "you" to "your" in the third sentence.

 

[TheParser]

***** NOT A TEACHER *****


Hello, Creamcake:

I have found some extra information that may interest you.

One scholar is very upset because he says that some native speakers do not know the difference between "might have" + past participle and "may have" + past participle.

Based on his ideas, I have made up these sentences:

1. TheParser might have lived if the ambulance had arrived on time. By the time it arrived, however, TheParser was dead.

2. There's been a plane crash. TheParser may have lived through it, but we're not sure yet.


The scholar gives this "rule":

Might have + past participle = could have happened but didn't.
May have + past participle = could have happened but we don't know yet.

Credit: John Honey, Language is Power (1997), pages 158 -159.