I'm trying to get away from my arrow use but there is one thing I've yet to solve without using the arrow keys. Take this example:

```
var1 = "1"
var2 = "2"
var3 = "3"
var4 = "4"

```

Now I want this to be:

```
var_1 = "1"
var_2 = "2"
var_3 = "3"
var_4 = "4"

```

Using arrows I would just goto the var1, insert and add the underscore and then arrow down and do the same thing. The problem with using hjkl is I can't be in insert mode so I have to esc out, move down, insert...rinse repeat which required more work. Is there another way to accomplish this?