to "go about" something, as in, "She began to go about her day."

She began to do the things she needed to do that day.

to "go after" something, as in, "He will go after the prize."

He is going to seek the prize or try to get the prize. 

to "go back on" something, as in, "She went back on what she had agreed on."

She changed her mind and did not follow through with what she had agreed on.

She walked backwards after she agreed with me.

to "go by" someplace, as in, "Let's go by your house to get an umbrella."

Let's go to your house for a short amount of time just to get an umbrella.

Let's go to a shop near your house to buy an umbrella.

for something to "go without saying," as in, "It goes without saying that you need to look both ways before crossing the street."

It is self-evident (it doesn't need a person to say it aloud) that one should check the road before stepping into it.

You don't have to speak out loud when you look for cars on the street. 