"It's quarter past six." in Italian is

Sono le sei e un quarto.

Definitions

Analysis
sono
1. v. first-person singular present of essere; (I) [[am]], [[I'm]].
2. v. third-person plural present of essere; (they) [[are]], [[they're]].
3. n. alternative form of suono
essere
1. v. (intransitive, indicating existence, identity, location, or state) to be, to stay
2. v. (auxiliary, used to form composite past tense of many intransitive verbs) to have (done something); to
3. v. (impersonal, of a duration of time since an event) to have passed
4. n. being
Le
1. pron. (formal) alternative case form of le (you)
nel ringraziarla per la sua risposta, Le porgo i miei distinti saluti
2. art. the
3. pron. (accusative) them (third-person plural feminine)
Le ho viste. - I saw them.
sei
1. num. (cln, it, cardinal numbers) six
2. adj. six
3. n. six
4. n. (following the article le) six o'clock (a.m. or p.m.)
Sono le sei. - It's six o'clock.
essere
1. v. (intransitive, indicating existence, identity, location, or state) to be, to stay
2. v. (auxiliary, used to form composite past tense of many intransitive verbs) to have (done something); to
3. v. (impersonal, of a duration of time since an event) to have passed
4. n. being
e
1. conj. and
un
1. art. an, a
2. n. one
3. adj. one
4. pron. one
quarto
1. adj. fourth
2. n-m. fourth (the one in fourth position)
3. n. fraction; part of a town, fraction