Co oznacza "I'd" w zadaniu: I couldn't stand doing my homework, so I'd just go to class without it.

Cześć

Tak jak napisałeś I would = I'd.

I'd jest skróconą formą od I would (tzw. contraction)
I'd is the contraction of I would

ale, I'd może również oznaczać I had w zdaniach z past perfect, np:

If I'd known you were in trouble, I'd have come to help.
If I HAD known you were in trouble, I WOULD have come to help.

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