used at the beginning a question.
Est-ce que tu viens ? will you come ?
Est-ce que tu aimes les chiens ? Do you like dogs ?
Two ways to ask question (grammaticaly correct)
Est-ce que + suject +...
The phrase 'qui est-ce' means Who is it? In the word-by-word translation, the interrogative pronoun 'qui' means 'who'. The verb 'est' means '[he/she/it] is'. And the demonstrative pronoun 'ce' means...