1. Is the following sentence acceptable?
2. Which is acceptable, 'drug abuser' or 'drug addict' ?
3. What does it mean by the phrase 'going through withdraw'?
The drug abuser/addict is going through withdraw.
1. This part of your post is unnecessary.
2. A "drug abuser" is somebody who uses any drug, whether it is legal or not, in an excessive way. A drug abuser does not necessarily become an addict.
A "drug addict" is a drug abuser who eventually becomes mentally and physically dependent on a drug, they cannot do without it.
3. When a drug addict stops taking the drug and tries to give it up, their body will often go through a period of very unpleasant reactions that can make the process painful and difficult. This period is called the "withdrawal" (note the spelling).
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