You can't have two imperative verbs in a row, just as you can't have two present-tense verbs in a row. Like in the sentence "mi volas esti alta" (I want to be tall). If you tried to say "Mi volas estas alta", it would be wrong. In the sentence above, "be" is subordinate to "please" so it must take the infinitive form. If you really want to say "estu" you could rewrite "please" as an adverb and the sentence would be "Bonvole estu atenta". This form is less common but it is grammatically correct. "Bonvolu esti atenta" could be translated as "Be so kind as to be attentive" where "Bonvole estu atenta" would be more like "Kindly be attentive".
Oooh… so "bonvolu" is actually a verb? No wonder why I was confused! Thanks! :)
This response is so informative and helpful. Cleared all sorts of things up for me. Thanks!
But, if you divide the sentence into two parts, it iwill be also correct. Just use a comma between!
Bonvolu, estu atenta!
atenta : "in alert" atendanta danĝeron, kiu povas aperi en iu ajn momento.
zorgema : "who takes care", kiu zorgas, ekzemple por ne rompi, ne difekti, ne maltrafi ion.
Se oni volas diri "Please be more careful", povas oni diras "Bonvolu esti pli atenta?"
Gramatically that's fine. One could argue that there's a slight difference between "Bonvolu atenti" and "Bonvolu esti atenta" just as there's a slight difference between "Please pay attention" and "Please be attentive" but the difference in nominal.
Because, in the imperative form, if the subject is not mentioned, it's understood to be
"vi estas atenta" -> "vi estu antenta" -> "estu atenta"
This is different from the impersonal verbs, which don't need a subject at all:
"estas varme", "necesas, ke ...", k.t.p
I hope it helps. :)
If we want to split hairs, there's nothing grammatically wrong with that. After all, an adverb modifies a verb. You do say things like "Kuru rapide". But it might change the meaning. The sentence "estu atente" would translate as "be attentfully".
Thanks for your clarifying. But the question was about why "atenta" not "atente". As you said, both are grammatically correct, but the meaning may be different. :)
No problem at all. We both gave correct answers. You just answered why is it "atenta" and I answered why isn't it "atente". :)
Does this also mean "Please pay attention"? If so, how in Esperanto, do we distinguish between the two english statements that have quite different meanings?
I would understand it to mean both "Please be careful" and "Please pay attention", but I also don't think they have that different of a meaning, per se. If you want to say "Caution" you could say "Singardo" and "Danger" is "Dangero", so if the shades of meaning are important to you, you can use those words instead of atenti: "Esti singarda!"