英和和英

half-yearly―semi-annually

half a year―a half year

per annum

the period of half a year

a duration of one year

In one year

the time period within the span of a year

year-round

every half year, every six months

twice a year

a time period of a year

a period of one year

half-yearly―semi-annual―biannual

one year

yearly―annual

over a 2-year period

for a few years

throughout the year

once a year

for a year

after a year―a year after―a year later

Once a year

half-yearly―biannual

twice a year―half-yearly―semi-annually―biannually

one whole year

throughout the year

Two years.

How many years?

for two years in a row

by the year