YOU SAID:
self talker better shut his mouth or ill shut myself
INTO JAPANESE
自己話し手は自分の口を閉めたり自分自身を閉めたりする
BACK INTO ENGLISH
Self-talker closes his / her mouth or closes himself / herself
INTO JAPANESE
自己話し手が口を閉じたり、自分を閉じたりする
BACK INTO ENGLISH
Self-speaker closes mouth or closes oneself
INTO JAPANESE
自己話し手が口を閉じたり、自分を閉じたりする
BACK INTO ENGLISH
Self-speaker closes mouth or closes oneself
You've done this before, haven't you.