segundos in twenty seconds, in thirty seconds' time
minutos in a minute, in ten minutes, in ten minutes' time
horas in an hour, in ten hours, in ten hours' time
dias in two days, in thirty days' time
semanas in a week, in two weeks, in two weeks' time
meses in a month, in two months, in a month's time,
in January, in July, in May 2000, in June 2001
anos in 1959, in 1980, in 1999, in 2001
décadas in the 1960s, in the 1970s, in the 1990s
séculos in the 19th century, in the 21st century
partes do dia in the morning, in the afternoon, in the evening,
in the night (1)
estações in (the) spring, in (the) summer,
in (the) autumn, in (the) winter
festivais in Easter week, in Ramadam
períodos in that time, in that year, in that period
dias da semana on Sunday, on Monday, on Tuesday,
on Sundays, on Mondays, on Tuesdays
partes do dia on Sunday morning, on Monday afternoon,
on Wednesday evening
datas on 21st January, on June 10th,
on 2nd May 1990, on 30th June 2000
aniversários on my birthday, on our wedding day
festivais on Christmas Day, on New Year's Day,
on Good Friday, on Easter Sunday
acontecimentos on that day, on that afternoon, on that evening
festivais at Christmas, at Christmas-time, at Easter
horas exactas at seven o'clock, at twelve thirty, at 3.30 p.m.,
at midday, at midnight, at noon
idades at sixteen, at the age of 18
outras at dawn, at this time, at that time, at tea time,
at lunch time, at dinner time, at the weekend,
at night (2)
all all morning, all day, all week, all month, all year
every every morning, every day, every week
last last night, last Friday, last week, last month
next next Friday, next week, next month, next year
tomorrow tomorrow, tomorrow afternoon
yesterday yesterday, yesterday morning
outras the day before yesterday,
the day after tomorrow
(1) in the night refere-se a uma noite específica
(2) at night refere-se a uma noite como uma outra qualquer