Is this an imperative? There was also an -αι ending that was a first person singular indicative, wasn't there?
So, is there a class of verbs that have α in the endings and no ς on the 2nd person singular?
Yes, passive verbs (ending in -μαι.) Pe: (remember) Θυμάμαι/θυμάσαι/θυμάται/θυμόμαστε/θυμόσαστε-θυμάστε/θυμούνται. Note that an active similar verb exists too θυμίζω (remind) that follows the normal rules for verbs that end in -ω
I'm glad you pointed the last part out, or I would have thought it just deponent.
Θυμάμαι is deponent. I just wanted to separate it from the other same-looking active voice verb. I edited my previous comment so it is clear. :)
OK, the Wikipedia article JacobPast177 linked, though, seems to indicate that Modern Standard Greek has this mediopassive form, that includes not only what one would consider deponent in Ancient Greek, but also the middle voice. Honestly, I just wanted to know whether there were just some fundamentally different conjugations in the indicative active, and to see how this thing was conjugated.
And that, of course, is what I was seeing in another one of these sentences. It is a subjunctive, right?
Yes, you are right, my fault. Θυμάμαι has no imperative of the present tense (προστακτική του ενεστώτα), i.e. of the imperfective aspect, so the subjunctive of the present tense (υποτακτική του ενεστώτα) is used instead. I hope I'm getting the grammatical terms right, since I mainly learned Greek here in Greece just by talking to people, and only a little from textbooks.
Please, don't apologize. It is we how are at a disadvantage, just trying to understand what you undoubtedly learned just by trying.
There is no question mark on the Greek sentence, so why translate it as a question?
Θυμάμαι is a déponent verb: it is conjugated like a passive verb but it's meaning is active. There seems to be quite a few of those in Greek
Why is 'recall' marked wrong? 'You recall the boy' is an accurate translation, but Duo rejects it.