Since and Because

"Since” refers to time. “Because” refers to causation. e.g., Since I quit drinking I’ve married and had two children. e.g., Because I quit drinking I no longer wake up in my own vomit.

Disinterested and Uninterested

Contrary to popular usage, these words aren’t synonymous. A “disinterested” person is someone who’s impartial. For example, a hedge fund manager might take interest in a headline regarding the performance of a popular stock, even if he's never invested in it. He’s “disinterested,” i.e., he doesn’t seek to gain financially from the transaction he’s witnessed. Judges and referees are supposed to be "disinterested." If the sentence you’re using implies someone who couldn't care less, chances are you’ll want to use “uninterested.”

Anxious

Unless you’re frightened of them, you shouldn’t say you’re “anxious to see your friends.” You’re actually “eager,” or "excited." To be “anxious” implies a looming fear, dread or anxiety. It doesn’t mean you’re looking forward to something.

Different Than and Different From

This is a tough one. Words like “rather” and “faster” are comparative adjectives, and are used to show comparison with the preposition “than,” (e.g., greater than, less than, faster than, rather than). The adjective “different” is used to draw distinction. So, when “different” is followed by a preposition, it should be “from,” similar to “separate from,” “distinct from,” or “away from.” e.g., My living situation in New York was different from home. There are rare cases where “different than” is appropriate, if “than” operates as a conjunction. e.g., Development is different in New York than in Los Angeles. When in doubt, use “different from.”

Bring and Take

In order to employ proper usage of “bring” or “take,” the writer must know whether the object is being moved toward or away from the subject. If it is toward, use “bring.” If it is away, use “take.” Your spouse may tell you to “take your clothes to the cleaners.” The owner of the dry cleaners would say “bring your clothes to the cleaners.”

Impactful

It isn't a word. "Impact" can be used as a noun (e.g., The impact of the crash was severe) or a transitive verb (e.g., The crash impacted my ability to walk or hold a job). "Impactful" is a made-up buzzword, colligated by the modern marketing industry in their endless attempts to decode the innumerable nuances of human behavior into a string of mindless metrics. Seriously, stop saying this.

Affect and Effect

Here’s a trick to help you remember: “Affect” is almost always a verb (e.g., Facebook affects people’s attention spans), and “effect” is almost always a noun (e.g., Facebook's effects can also be positive). “Affect” means to influence or produce an impression — to cause hence, an effect. “Effect” is the thing produced by the affecting agent; it describes the result or outcome. There are some exceptions. “Effect” may be used as a transitive verb, which means to bring about or make happen. e.g., My new computer effected a much-needed transition from magazines to Web porn. There are similarly rare examples where “affect” can be a noun. e.g., His lack of affect made him seem like a shallow person.