是： am ( 我是Youali / I am Youali）
yes, I see ect.
十： ten 十一 eleven, 二十一 twenty one
师： it means somebody who can teach something or master some know-how.
it always appear to be phrase with other words, such as 老师teacher, 工程师 engineer
识： means know. 认识：know 识别 recognize
means know some truth, 知识：knowledge 常识：common knowledge