Learn Spanish (Latin America): Agradeceríamos que el experto tasara la moneda cuidadosamente. - We would appreciate it if the expert appraised the coin carefully.

The main verb, agradeceríamos, is in the conditional tense. When you make a polite request or express an emotion using the conditional, the verb in the dependent que clause must be in the imperfect subjunctive to match that hypothetical or softened tone.

The English translation uses 'if', but the Spanish uses que. Why don't we use si?

English uses 'if' for these polite requests, but Spanish uses a standard noun clause starting with que (that) when there is a change of subject. With verbs of emotion or preference like agradecer or gustar, using si sounds like a direct translation from English. You should use agradeceríamos que plus the subjunctive.

Could we use tasase instead of tasara?

Yes, tasase is the alternative form of the imperfect subjunctive and means exactly the same thing. However, in Latin America, the -ra endings like tasara are much more common in both spoken and written language.

Is agradeceríamos an expression of influence or emotion here?

It functions as a bit of both! Agradecer means to appreciate or be grateful for, which is an emotion. However, in this conditional form, it is used as a polite way to make a request or suggest an action, which makes it an expression of influence. Both types of triggers require the subjunctive.