"The man is ugly."
Translation:La viro estas malbela.
"malbelas" means "is ugly". Both solutions are equally correct. Adjectives can be changed into verbs to avoid the use of "estas"
Well, not really. If you say "la viro malbelas", then it's something he does. Like "La kato kaptas la muson" is something the cat does. The -as ending is the present tense verb. You could say "the man is (doing) ugly", but I don't think that is what you want to say here. "La viro estas malbela" = "The man is ugly" is like a characteristic of how the man is or how he looks - and he really is ugly... ;-) Ĉiu povas vidi ke la viro estas malbela, stulta, dika kaj riĉa. Li estas la ĉefo de Norda Koreio.
No, this is incorrect. As said above, "La viro malbelas" means "the man is ugly."
"The man is being ugly" is an English idiom which really means "the man is behaving in an ugly fashion," which means he is perhaps screaming and throwing things, or being mean to someone. In any case, if you know the idiom, the phrase "the man is being ugly" means a lot more than the literal translation of the words. So it isn't a good example here.
Try "la roza belas" instead: "the rose is being beautiful." It's pretty much equivalent to saying "The rose is beautiful," isn't it?
An even closer English translation would be "the rose beautifuls" except we don't do that in English.
The verb would have to be there to make sense. "La viro malbela" translates to "The ugly man". "La viro estas malbela" is just more correct.
NB: "la viro malbela" is a (slightly)different sentence from "la viro malbelas"
"the ugly man" vs "the man is ugly"
La viro malbelas would probably be translated closer to "The man is being ugly".
How come that in some sentences there are "la" and "le" but in others there aren't. What is the rule?
La is a definite article, which is referring to a specific thing.
"La viro" = "The man"
"Viro" = "A man"
why we cant use "la viro malbela estas"? why all the grammer of spranto as the same as western languages?
The verb "estas" is one of the few times that the order of the subject and object really matters. In many sentences, as you will see later, the direct object ends with -n, so "La viro aĉetas fruktojn" literally means "The man buys fruit." In this case, since the suffix -n has to be used, you could easily change it around. "La viro fruktojn aĉetas," or "Fruktojn aĉetas la viro," or a few other options would still make sense. In the case of the verb "estas," you never use -n (except for a few very specific exceptions, they are explained later in the course). Because of this, the order must remain as "[Subject] estas [Adjective/adverb]."
If you have any more questions, please don't hesitate to ask! I have been learning Esperanto for a pretty long time, and though I am not fluent, most of the grammar rules are explained early on (I just need to work on my vocabulary!).