Ordinal numbers indicate the position that an element occupies within an ordered series. These numbers can be expressed in words (first, second...) or in an abbreviated form (1st, 2nd...)

2. One-digit numbers

The first three numbers have the endings -st, -nd, -rd.

However, from the fourth onwards, we will take the cardinal number and we will add the ending -th to it.

CARDINAL NUMBER

+ th

ORDINAL NUMBER

3. Aspects to be taken into account

In the tens ending in zero, the -y is replaced by an -i and then the ending -eth is added.

CARDINAL NUMBER

ORDINAL NUMBER

In the tens containing numbers 1, 2 and 3 we will add the ordinals first, second and third to them respectively.

CARDINAL NUMBER

ORDINAL NUMBER

Numbers 11, 12 and 13 do not follow the same pattern. They end in -th:

I live on the eleventh floor.

Her birthday is on twelfth of August.

4. How are ordinal numbers used?

To define the position of an element within a sequential order.

- How is the race going?

- Pedrosa first, Márquez second.
With dates, to indicate the specific day of a month.

- What day is it today?

- Today is the 7 ^th of August.
To indicate a century or one of the levels in a building (floor).

This is the best invention of the 19 ^th century.

John's room is on the seventh floor.
To indicate the anniversary year of something or someone.

- What are they celebrating?

- Their fiftieth wedding anniversary.
To refer to a king, queen or pope.

- Who is that woman?

- Elizabeth II Elizabeth the Second.