Split infinitives are, after passive voice, a grammatical construct that calls for the most pissed off responses from either side of the argument. A split infinitive means to literally split the infinitive (the verb form preceded with to) and stuff another word or phrase inside. Take to triple. That's an infinitive verb. Now let's murder that son of a bitch: Apple stocks are expected to more than triple in profits. Doesn't that feel fine? And, since every article that discusses split infinitives uses the next example, so will I: To boldly go where no man has gone before.
The craze against split infinitives started when someone decided that English should follow Latin grammar; Latin infinitives are one word (e.g. videre = to see). It would be stupid to split a word in two and stuff something else inside, wouldn't it? But if you do, call it tmesis, and it becomes a literary device. I leave it to the reader to decide whether it makes sense to place the grammar of an old language upon a modern language. But if you say yes we better also love passive voice, because Vergil and those poetic Latin authors used it every chance they had. (When it comes to passive voice, English classes teach bugger all, but Latin clears it up good.)
Whether to capitalize north or south or northern or southern can seem complicated. Why do we say north of the lake but meet me in the North, or northern winds but Southern Hospitality? As with most things in the world of grammar, there are a few rules to help us out.
Rule 1: Capitalize north, south, east, west, and their derivatives when belonging to proper names or when used to signify specific regions: I live in the North, North Pole, Southern Hospitality, West Coast, down South.
Rule 2: If the words indicate a direction, do not capitalize them: I lived in the south of Germany, drive west on this road until you hit the stop sign.