Questions & Answers about Pedimos ayuda y nos echaron una mano.
Both are in the pretérito (the simple past), which is the tense Spanish usually uses for completed actions in the past.
- pedimos = we asked
- echaron = they gave / they lent in this idiomatic expression
In this sentence, the speaker is talking about two finished events:
- We asked for help
- They gave us a hand
So the preterite is the natural choice.
Spanish forms can sometimes look the same in different tenses. Pedimos can be:
You know which one it is from the context. Since the second verb is clearly past (echaron = they gave), pedimos is also understood as past here.
So in this sentence, pedimos ayuda means we asked for help, not we ask for help.