ante meridian (a.m.)

From 12.00 in the middle of the night till 11.59 morning before noon.

used when referring to a time between twelve o'clock at night and twelve o'clock in the middle of the day:

The first election results are expected around 1 a.m.

post meridian (p.m.)

From 12.00 at noon, afternoon, evening till 11.59 at night

used when referring to a time in the afternoon or evening or at night:

We'll be arriving at about 4.30 p.m.

The 6 p.m. train is usually very crowded.

answer

Exercise 5