My English teacher likes watching TV.
1,这里出现了两个动词 is 和like,你要表达的意思是喜欢,所以用like,My Englis teacher是第三人称单数,所以用likes.
2,like后面要跟to do sth或doing sth.根据以下可知这里要用doing,因为表示的是爱好.
当表示喜欢某事物,而且以前就喜欢,还可能持续,用like doing ,如：He likes cooking in his house.
She likes singing.这些都可以表示一个人长期的爱好.
当表示想要,欲做某事用like to do,例如：He likes to cook in his house.-他想在自己家做饭吃.
She likes to stay with us.-她想和我们带一块儿.（以前想不想我们无法知道）.