Unit 121. At / on / in (time)

Complete the sentences. Use at, on or in + the following:
Key.2   at night
3   in the evening
4   on 21 July 1969
5   at the same time
6   in the 1920s
7   in about 20 minutes
8   at the moment
9   in the Middle Ages
10 in 11 seconds
11 (on) Saturdays

the evening    about 20 minutes    1492             the same time the moment   21 July 1969           the 1920s      night Saturdays      the Middle Ages     11 seconds

1    Columbus made his first voyage from Europe to America    in 1492     .   
2    If the sky is clear, you can see the stars ___________.
3    After working hard during the day, I like to relax ___________.
4    Neil Armstrong was the first man to walk on the moon ___________.
5    It's difficult to listen if everyone is speaking ___________.
6    Jazz became popular in the United States ___________.
7    I'm just going out to the shop. I'll be back ___________.
8    (on the phone)  'Can I speak to Dan?'    'I'm afraid he's not here ___________.
9    Many of Europe's great cathedrals were built ___________.
10  Ben is a very fast runner. He can run 100 metres ___________.
11  Liz works from Monday to Friday. Sometimes she also works ___________.

Put in at, on or in.
Key.2  I last saw her on Tuesday.    or  I last saw her Tuesday.
3   in
4   At
5   on
6   in
7   in
8   at
9   on
10 at
11 in
12 at
13 on
14 in
15 On Saturday night    or   Saturday night ... at midnight
16 at 5 o'clock in the morning
17 on 7 January ... in April
18  at home on Tuesday morning.    or   at home Tuesday morning  ... in the afternoon

1    Mozart was born in Salzburg    in     1756.
2    I haven't seen Kate for a few days. I last saw her ________ Tuesday.
3    The price of electricity is going up ________ October.
4    ________ weekends, we often go for long walks in the country.
5    I've been invited to a wedding ________ 14 February.
6    Jonathan is 63. He'll be retiring from his job ________ two years' time.
7    I'm busy just now, but I'll be with you ________ a moment.
8    Jenny's brother is an engineer, but he doesn't have a job ________ the moment.
9    There are usually a lot of parties ________ New Year's Eve.
10  I don't like driving ________ night.
11  My car is being repaired at the garage. It will be ready ________ two hours.
12  The telephone and the doorbell rang ________ the same time.
13  Mary and David always go out for dinner ________ their wedding anniversary.
14  It was a short book and easy to read. I read it ________ a day.
15  ________ Saturday night I went to bed ________ midnight.
16  We travelled overnight to Paris and arrived ________ 5  o'clock ________ the morning.
17  The course begins ________ 7 January and ends sometime ________ April.
18  I might not be at home ________ Tuesday morning, but I'll be there ________ the afternoon.