Hola, Each of these three verbs have many meanings. I'll try to explain as a native American English speak how I think of these three verbs. [Note, I don't speak Spanish but I used google translate to help make my point. My apologies for any errors]. 1) To Support (I think this verb has the most meanings) a. the most common meaning in my opinion is in the physical sense. The ability to hold weight. For example, "the walls supports the roof [las paredes soportan el techo]" or "the rope supports the climber [La cuerda sostiene al escalador]". b. the other meaning of "to support" can mean "to help". For example: "the voter gave money to support the mayors election [el votante dio dinero para apoyar la elección de alcaldes]". 2. To bear: this word also has many meanings in English. However, this isn't a word that you will use in modern spoken English frequently. However, to answer your question, you can use the verb "to bear" as a synonym for "to withstand". But, the difference in my opinion is: a. "to bear" can express an emotion. For example: "I can't bear the thought of my wife dying [No puedo soportar la idea de que mi esposa muera]." However, nobody would say " I can't withstand the thought of my wife dying." b. "to withstand" more often expresses a physical state. For example: "the walls and roof withstand the wind of the hurricane". I hope this helps.