himself or themselves

Use myself, yourself, himself, herself, itself for one person or thing. These words say that the same person does it and gets it.

Use ourselves, yourselves, themselves for more than one. Always say himself and themselves, never hisself or theirselves.

🔹 Tom hurt himself with the hammer.

🔹 The workers protected themselves from the dust.

himself or him

Use myself, himself, herself when the same person does the action and gets the action. I taught myself.

Use me, him, her when it is a different person. Say "She helped him", not "She helped himself".

🔹 I taught myself to use a drill.

🔹 She helped him drill the hole.

by myself = alone

by myself or by yourself means alone, with no help. We can also say by himself, by herself, by ourselves or by themselves.

It goes at the end: "I fixed it by myself." It says that nobody else did the job. Do not say "by me".

🔹 My sister fixed the leak by herself.

🔹 Did you tape the crack by yourself?

each other

each other is for two or more people who do the same thing to one another. Person A helps Person B, and Person B helps Person A.

Say each other for this. Do not say themselves: "They helped themselves" means each person helped only himself or herself.

🔹 The two brothers hold the ladder for each other.

🔹 They showed each other how to measure the wall.