Translation:We would be glad if you worked more.
The historical construction of the subjunctive might help you with how it's more commonly used now. A hundred years ago, this sentence would probably have been constructed like this: "It would be good if you were to work more." That's the subjunctive form of "were", still in use in written and more formally correct spoken English - "it would be good if he were nicer", which in a lot of spoken UK English now is more likely to be rendered as "it would be good if he was nicer" - as people mistake the subjunctive for a past tense and so adjust it from "were" to "was" to fit their understanding of the subject of the thought as singular - as discussed elsewhere on these forums.
In the same way, over time, people have mistaken the "were" in the construction "it would be good if you were to work more" for a past tense and then have allowed that past tense to "slip" to the active verb, creating "it would be good if you worked more". And, as VladaFu says, that's become the default construction for the second conditional in most cases - one clause with would and one with a simple past tense.
That might be of no use to you at all - but I sometimes find the journey of language over time helps me get to grips with where it's at now!
The little I remember from my English lessons (most on my own money) says that the dependent clause uses the subjunctive (often identical to the imperfect) while the main clause uses “would”. But who am I to argue…
And of course it would be different if it were about a present or future condition (we will be glad if you work more). But are we studying English or Czech? Or whatever.…