Answer:
1.- hiciera
2.- supiera
3.- fueran
4.- termino
5.- aumentara
6.- tuviera
7.- llamas
8.- trabajaba
9.- hacía
10.- sabes
Explanation:
1.- This is a conditional sentence about an unreal situation. In English, we'd say: <em>"If Elena did her job better, she could ask for a rise"</em>. The form of the verb expected in an <u>if clause</u> in Spanish, in this type of conditional construction is subjuntivo (subjunctive), which is used to refer to a hypothetical event. The infinitive is 'hacer' and the subjunctive 'hiciera' (singular)
2.- Since this one is another <u>if clause</u> about a hypothetical situation in the present, a subjunctive form is expected here again. Notice that <em>subjuntivo</em> is a form, which can have different endings depending on the tense. The one used for this kind of construction is "Subjuntivo imperfecto". You can easily find a conjugation dictionary online. The infinitive is 'saber' and the subjunctive 'supiera' (singular)
3.- Another unreal or hypothetical situation: "If you <u>attended</u> the meetings, you would understand the changes in the company." The if clause expects a subjuntivo imperfecto. The infinitive is 'ser' and the subjunctive 'fueran' (plural).
4.- Now we have another conditional, but this one refers to an event in the present on which an future event depends. This type of construction is easier, the expected form of the verb is simple present.
5.- Another one just like 1, 2 or 3: the expected form is a subjuntivo imperfecto: The infinitive is 'aumentar' and the subjunctive 'aumentara' (singular)
6.- Same case as in 1-3 and 5: A hypothetical situation. The infinitive is 'aumentar' and the subjunctive 'aumentara'.
7.- Another sentence that has the same structure as number 4: An action in the present that conditions another in the future: <em>"If you call me in the morning, I'll give you your books in the afternoon"</em>. The form we expect here is just a present form. The infinitive is 'llamar' and the subjunctive 'llamas' (2nd person, plural)
8.-Now we have a time clause. The verb forms correspond to <em>imperfecto </em>which is used to refer to the past, but the difference from the usual simple past, this form adds a sense of duration to the verb.
9.- Another conditional but now about the past, and again we find the <em>imperfecto</em>. The two clauses refer to events or actions that 'used to happen': Si los domingos <u>hacía sol</u> = If the day <u>was sunny</u> on Sundays; mi padre siempre nos <u>llevaba</u> a la playa = my dad <u>would </u>always<u> take</u> us to the beach.
10.- A conditional that works exactly the same as the zero contitional in Enlgish: If you know the answer, don't hesitate to rise your hand. The form of the verb is present.