Two conjugations?

Question

In the question, Yo ________ llegado pronto a trabajar esta tarde, why is llegar conjugated? I thought if the first verb ( in the blank is the conjugated form of  haber) is conjugated the second verb is left in the infinitive form.

Inma Sánchez · Accepted Answer

Hola Mollie
The auxiliary verb haber is used to form the present perfect tense of other verbs, i.e. to say I have gone, you have done, he has worked, etc.. 
The first part of the present perfect structure is the verb haber in the present, as in saying: I have..., you have..., he has... and then the second part is the main verb in the past participle form: ido, trabajado, tenido...etc. Here, in this lesson we are only testing the first part of the verbal structure, the part with haber: he, has, ha, hemos, habéis, han. 
So here in this sentence you need:
Yo he llegado pronto a trabajar esta tarde.
I hope this clarified it.
Saludos
Inma

Zenepe Beqiraj · Answer

Yo hay llegado pronto a trabajar esta tarde