used when the subject of the verb is "I" and the object is the same person

I bought myself a new coat. 我为自己买了一件新外套。

I caught sight of myself in the mirror. 我在镜子中瞧见了自己。

Yes, I thought to myself, it's time to take a holiday. 是啊，我自己思忖着，是该休个假了。

used to emphasize "I" as the subject of a sentence

I myself don't like a heavy meal at lunchtime. 我本人不喜欢午饭时吃很多。

I don't like a heavy meal at lunchtime myself. 我自己不喜欢午饭时吃很多。

used instead of "I" or "me"

My husband and myself were delighted with the gift. 我和丈夫收到这份礼物都很高兴。

They very kindly invited my sister and myself to the inauguration. 他们盛情邀请我姐姐和我参加开幕式。

alone or without help from anyone else

I live by myself . 我自己单独住。

I had to do the whole job all by myself . 我不得不独立完成所有的工作。

I'm ashamed to say I ate the whole plateful all by myself.

Are you going to leave me all by myself?

I don't especially like travelling by myself.

I managed to take a shower by myself for the first time since the operation.

I can't move all those boxes by myself.

for my use only

I never get an hour to myself. 我从没有属于自己的一个小时的时间。

I had a couple of hours to myself between appointments so I thought I'd visit the cathedral.

I usually get an hour or so to myself before the rest of the family get up and I love it.

I had a double room all to myself and it was wonderful.

For half an hour I had the whole pool to myself.

So I get to have you all to myself this evening, do I?

not to be or feel as happy or as healthy as usual

I'm sure you're aware that I haven't been myself lately.

I went to see the doctor because I haven't been quite myself lately.

I'm normally pretty upbeat but I really haven't felt myself since the news.

US I don't know how else to put it except that I haven't been feeling like myself.

Since the accident I haven't felt myself.

US I thought I was doing better, but I still don't quite feel like myself yet.

used when describing your state of mind when you are physically ill

I'm well enough in myself (= happy) - I've just got this nagging headache. 我精神状态很好——只是这头痛的毛病一直没好。

I've definitely been feeling better in myself these last couple of days.

I've felt better in myself since I changed my diet.

I feel a lot better in myself and I put that down to my new regime.

I'm still quite tired but definitely better in myself.

keep (myself) to myselfidiom 不常与其他人交谈