One way to look at language as a phenomenon is to realise that it solves problems.
That ‘problem’ is communication, and so language solves a set of problems that range from the most simplistic (I want you to give me a rock), to the incredibly complex (I want you to have the same knowledge of Hindu ontologies that I do). But whatever it is, it’s a problem for which language provides a tool to solve.
If you think of language this way, it also helps makes sense of why languages are so similar – they have to solve the same set of problem-types. There might be infinite ‘problems’, i.e. infinite purposes to which you can apply language, but they ultimately can be typed as a finite set of purposes or problems. And so we can classify language patterns across languages by what they solve.
For example, things that generally fall under the ‘Imperative’ label solve a fairly basic problem: how do I tell you I want you to do something? I use something that functions as an imperative.
This is a good example to talk about. Let’s say I’m sitting at dinner with you and I want you to pass the salt.
I might say, “Pass the salt”. We would call this, grammatically, an imperative. But English linguistic cultures generally don’t like plain imperatives.
We might instead say, “Please, pass the salt.” I don’t know what grammarians call ‘please’; we could analyse it historically and etymologically, and talk about, ‘if it please you’; or we could talk about it functionally and say that it softens the directness of the imperative.
Or we might say, “Would you please mind passing the salt”, in which case we have added a verb (“mind”) and a modal phrase (“would”) to make the imperative more indirect. Grammatically most people would not parse this out as an imperative. But it’s functionally an imperative.
Now, when you come to a different language, you can ask yourself this question, “How do I get someone to pass me the salt?”
Do you see how the problem gives you an acquisition tool? Or to rephrase, thinking of language like this allows you to set up situations to acquire language. Want to learn the imperative? Create situations where you can elicit it and where you can use it and be corrected.
Mongolian is an example close to my experience, and a good counter-example. It’s useless to translate something like, “Could you pass me the salt?”. You get something like Чи давс надад өнгөрөж болох уу? This is not even a proper sentence, because you can’t use ‘pass’ in that way. Nor something indirect like, “I would like the salt”. Even “I want to get the salt” is not appropriate, Би давс авмаар байна. In Mongolian this is an indicative statement that expresses the fact that you want the salt. There is no socio-linguistic sense that makes it an implied imperative. You are simply telling the other party about your volitional state.
To get the salt, you need to say something like давс аваад огооч, which translates as something like “take the salt and give [it]”. The combination of “take, then give” is the proper expression for the English “pass”, and the -ооч ending there is one form of imperative.
This is on the simple side of examples, but I’m trying to illustrate that thinking of language as a set of ways to solve problems allows you to:
1. Ask the question, “How does my language solve problem X?” often instead of “how do I translate X?”
2. Set up and look for situations that elicit certain structures, by thinking through what problems there are.