Question

it ........... for two hours.(rain) ​

Answer 1

was raining is the correct answer

Answer 2

Rained

Tense:

Tense is a category that displays a timeline. Times are often expressed through the use of certain types of verbs, especially in their combining patterns.

In this sentence, we are talking about something which will be done in the past. Hence, we have to use the past tense with the verb.

So, we will use "rained" in this sentence to complete it. Now the sentence will be "it rained for two hours".