Explications:
13h55:it!s five to two
14h: it's two o'clock
14h:10:it's ten past two
14h50:it's ten to three
15:20 it's twenty past three
15h40:it's twenty to four
16h:it's four o'clock
16h40:it!s twenty to five
17h:it's five o'clock
17h10:it's ten past five