In Numbers^x, Past tenses^x, Modal verbs^x

In the early Church , Christians would celebrate the anniversary of a martyr's death for Christ (known as the saint's "birth day") by serving an All-Night Vigil , and then celebrating the Eucharist over their tomb or place of martyrdom. In the fourth century, neighbouring dioceses began to...

JTT: "The possibility started yesterday. It therefore started in the past." But it has not come to fruition. It can have no past tense because nothing has past, ie. nothing has finished. How curious. A possibility has no past? Maybe I misremembered the conversation with Casi: ...

Only number 1 is correct. The main verb (the one that comes after the modal verb--will, would, could, can, etc.) is always in the infinitive (without "to"). Regarding to your second question, you must use a participle form of the verb to make compound tenses and not it's past tense form, as...