English often skirts around a given idea by utilizing many completely different words which have an indirect association of a given idea and occur as facets of it, as it were. Often the core idea does not even have a specific English word and may only be understood by an entire sentence needed to explain it.
Spanish is entirely different. It does not skirt around a given idea by hosting a variety of nuances relative a core idea. Instead, it utilizes the core key word directly and adopts it to all possible situations it applies.
For example, let's take the Spanish word, "duro."
What does duro mean? Duolingo simplies it by using the word, "hard." Whereas in English duro can mean,.hard, tough, harsh, difficult, stiff, severe, hardcore, strong, stale, stern, stubborn, unkind, intensive, adamant, hard-hearted, hard-boiled. Duro means all these total different English words. And they all together, combined, are what duro actual means.
To really understand what duro means at its core beyond the simple idea of its meaning, "hard," it is necessry to crunch all the various possible English translations together in one's mind, then mush them up running them in a blender, as it were, so you get a single flavored soup. Then you will have what the Spanish word means.
Look at the above list. Work out the common idea. You may see that it pertains to.something that cannot be changed. It innately resiststs being alftered in any way. It cannot be transformed. Or effected. And this enduring condition automatically naturally provides a sense of rigidity or firmness. This is what duro means and pertans to. And so the word, duro, can be used in any situation which this fundamental idea concerns. No variety of other words required Duro includes them all.
Many Spanish words work this same way.
English applies a variety of variations on a given theme, Spanish does not, but goes right to the heart of a matter. This is why it is a waste time, energy, and mental power focusing on the many different ways something can be said in English. The focus is best placed on understanding the all encompassing Spanish idea for which there often is no accurate English translation, but only words skirting it.
hope this helps
I'm with rspreng on this one. For adults with smartphones and computers, these sentences may seem a bit ridiculous. But my feeling is DL must teach us to crawl before we can walk. A child could conceivably make the mental leap that in order to accomplish a certain task or objective, "You open the door". The DL method of presenting us with sentences and phrases lacks the capacity to provide a full, deep and rich back story in which to set the context. So, I tend to go with the simplest translation that I think of to fit the spirit of the current lesson or my overall skill level that I happen to be at at the moment. Sometimes I'm right. Sometimes I'm wrong. Right or wrong, I then come to the comments to read my fellow classmates observations. In this case, I totally missed that this sentence could be read as a command. Thanks to all those who share their thoughts.
Not even that, a command doesn't necessary have to have exclamation marks in Spanish, but it has to be conjugated into the imperative form, also the subject tends to be invented with commands. For this to be the "tú" command, you would say "tú" not "usted": it would be "abre (tú)", not "usted abra". Also, the command form for "usted" would be "abra (usted)", the formal commands share conjugations with the subjunctive.
Usted is the formal counterpart of tú and it uses the third-person verb conjugations. This is because it was originally a contraction of "vuestra merced" which means "your mercy" and so it grammatically refers to the third-person object that you own, that is your mercy.
But you don't really need to memorize the history lesson. Basically just remember that usted uses the same conjugations as él/ella.
No, this is the "usted" form of the simple present tense.
If it said "Abre (tú) la puerta" or "Abra (usted) la puerta", then it would be a command.