Заполнить пропуски предлогами (at, in, on, up, by, from…till).
When is your sister`s birthday? My sister`s birthday is … the 10th … October.
I usually on watch …. 4 a.m. … 8 a.m.
Navigation usually starts … April, seldom … May.
We usually have a day off … the 1st of January.