Breakdown of Любое вложение должно оправдывать себя.
должен
must, have to
себя
oneself (себе: Dat/Prep)
любой
any
оправдывать
to justify
Questions & Answers about Любое вложение должно оправдывать себя.
The current lesson is about следует and стоит. Why does this sentence use должно, and could we use следует instead?
Должно is used here because вложение is the grammatical subject, and должно (a short adjective) must agree with it in gender. If you used the impersonal следует, the sentence structure would have to change. You would need the dative case for the logical subject: Любому вложению следует оправдывать себя. Using должно sounds more direct, like 'must' rather than 'ought to'.
Why is the imperfective verb оправдывать used here instead of the perfective оправдать?
This sentence states a general rule or principle: investments must always or continually justify themselves. When expressing a recurring expectation or a general characteristic rather than a single, completed action, Russian uses the imperfective aspect.
Could I use всякое or каждое instead of любое for 'any'?
Yes, they are very close in this context, but there are slight nuances. Любое means 'absolutely any (one you pick)'. Каждое means 'every (single one)', focusing on the individual items in a set. Всякое means 'any kind of' and can sound slightly more philosophical. For a business rule like this, любое is the most natural choice.
Why do we use себя for 'itself' instead of a pronoun like его?