0 hard and firm without holes or spaces, and not liquid or gas -- sólido
1 strong and not easily broken or damaged -- sólido
solid furniture
2 a substance or object that is not a liquid or a gas -- sólido
4 reliable and able to be trusted -- seguro/ra [ masculine-feminine, singular ]
a solid investment una inversión segura
a solid password to protect your computer una contraseña segura para proteger tu ordenador
solid information you can trust información fiable en la que puedes confiar
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Podemos completarlo paso a paso, por muy largo que sea el camino, y no se puede completar, por corto que sea el camino, si ni siquiera marcas tu huella.