It's important to recognize that "necessary" is usually used as an adjective although it can also be used as a noun (e.g. Food and water are a necessary for humans to survive." ) but usage as a noun is rare. Also, note that "necessary" conveys a fairly strong sense of need. When something is "necessary", it is more or less mandatory and not optional. Of course, the word can be used in situations where something is not *really* that necessary Example: "For her, it is necessary to put on her makeup before she goes anywhere, even to the mailbox in front of her house." (In her opinion, it is necessary but clearly that's just her way of doing things.) "Need" can be used as a verb or a noun and the strength of the need can be strong or weak. Example, "I need to brush my hair in the morning before I feel ready for the day." Example: "The perceived need to get constantly updated on the news of the world is a recent phenomenon." Important Notes: The nouns "need" and "necessary" are NOT synonyms! Also, the adjectives "needy" and "necessary" are also NOT synonyms. Finally, the verbs "to need" and "to necessitate" are NOT synonyms.

Normally and Usually are pretty much the same - it is HOW things are done most of the time. Generally, you refer to how a specific group tends to do something. Example: in general, we say things a certain way in English. Normally or Usually I always say it this way - which may be different from how the general public speaks.

"Necessary" is something that needs to be done to accomplish a goal, or something you need to live. Like air to breathe. "Need" is your feeling that something you must do something. Example: it may not be necessary to buy a new outfit but you need to since it's on sale!

"Sort of" is a way to explain something in a different way, but may imply some uncertainty of your understanding. When you say "Kind of" you are rephrasing to be understood. And that you know what you are talking about.