Good question! '因为...，所以...。因此...。' Following "因为", like 'because', a reason shoud be given out. After “所以”or “因此”, like 'so', there is commonly a related result caused by the reason. Moreover, "因此" also means as 'therefore', you can give out a conclusion based on all the arguments or facts given aboved.

when you come to a conclustion, you can use 因此 and 所以, they two are very close in concept. 因为is used when you explain somthing. For example: In the end of this month, all of my colleagues will go to Yunnan Province for traveling, but i canot join them. 因为(=because) i have to leave to take care of sths. First, someone has to stay in office to work, Secondly,i have been there years before. 所以or 因此，i determin to stay behind.

因此=所以 they r synonym.such as：i was blamed by boss,beause i missed a document.——因为我弄不见了一个文件，所以(or 因此) 我被老板责备了。=我被老板责备了，以为我弄不见了一个文件。

所以 and 因此 both can mean the result, but their usage is quite different. 所以 and 因为 is often used in one sentence while 因此 and 因为 can't be used in one sentence. Another difference is that 所以 can be used between subject and verb while 因此 doesn't have this usage. For example, 他之所以取得这么好的成绩，是因为他平时学习很努力。 As to 因为, it means because. Hope it helps!