Roro: A Motu-Type Austronesian Counting System

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Roro: A Motu-Type Austronesian Counting System

In this language:

6 is 3 pairs or 3 groups of 2,

7 is 3 groups of 2 plus 1

8 is 4 groups of 2,

9 is 4 groups of 2 and 1.

Counting by twos is common especially in ceremonies.

The counting system for Motu is similar except there is a special word for 7.

Background

This data as recorded by Lean comes from the four dialects of Western, Bereina, Eastern and Yule-Delena. It is also called Kivori, Maiva, Waima and Laval. Only the data compiled from 24 students by Lean is used here. It is fairly consistent with the old records of Lawes (1890), Ray (1895, 1927), Strong (1913) and Kluge (1940). Some students used a v rather than a b and a t rather than and h or they dropped the beginning h. Further details from Lean can be found in the appendix.

1	hamomo	1
2	rua	2
3	aihau	3
4	bani,	4
5	ima	5
6	abaihau	2x3
7	abaihau hamomo	2x3+1
8	ababani	2x4
9	ababani hamomo	2x4+1
10	harau haea	ten, one of
11	harauhaea hamomo	1 ten + 1
12	harauhaea rua	1 ten + 2
15	harauhaea ima	1 ten + 5
20	harau rua	ten, two of
30	harau aitau	3 tens
40	harau bani,	4 tens
100	sinabu, hinabu	a new word for hundred
200	sinabu rua	2 hundreds

The formation of the decades in Roro also has some interesting features.

10 arauhaia

20 arau rua

30 arau aitao

40 variabui

50 imabui

60 imabui arauhaia

70 imabui arau rua

80 imabui arau aitao

90 imabui arau variabui

The numerals 60 to 90 have the constructions respectively: 50+10, 50+20, 50+30, and 50+40. The Roro numeral 5 is identical to the word for hand, ima-, which takes possessive suffixes.

Lesson Plan

Subject: Cultural Mathematics

Grade: Elementary Two

Unit: Similarities and differences in our languages

Theme: Vernacular mathematics and English mathematics

Lesson Topic: How our words help us with English arithmetic

Objective: Students can explain the combinations of numbers up to 10 and then to 20 using the vernacular to make the combinations in English.

Preparation: At least 20 stones per student. Paper for recording or empty ten frames.

Set of large cards with 10 frames for 1 to 10, plus an extra 10.

Students can also have small sets of 10 frames and use these for representing the numbers instead of drawing them every lesson. The attachment is the appropriate set for this kind of language that uses doubles to make number words between 5 and 10..

Introduction and motivation

Give one card to each student from the sets of ten-frame, a symbol, vernacular word, or English word. Ask students to find their group (four per group) that match and sit down with them.

Ask each group of student to stand and show their cards and to say their vernacular and English words.

Collect the cards.

Explanation and Demonstration

Give out the sets of cards to each pair of students.

Count in the vernacular and stop at 6.

Students explain what the words for 6 mean in English

Students model the number 6

Students explain and model the number 7

Students should model six as 3 groups of 2 stones but they may model it as 2 groups of 3 stones.

They should add a single stone for 7.

Questions

What do the words mean for 6? Show me with stones? Show me on a diagram.

What do the words mean for 7? What do we do to these stones and diagram to make 7? Can we explain it another way?

Explain the lesson activity where students will write in English what the vernacular number words imply.

Student practice and activity

Students write 8 and 9 then the English words to explain its meaning and a diagram such as the ten frame pattern. Stones can also be used to model the numbers.

e.g., 9 is 4 groups of 2 add one.

9 = 2x3+1

9 is also one less than 10

Evaluation

Have students share their diagrams and writing. They might have written and said slightly different things but the meanings should be similar.

Questions

How did you record the number?

Did anyone record it differently?

If different ask, can you link these two ways together?

Explanation and demonstration

Discuss how the numbers for 18 and 19 are the 10 plus the previous set of 8 and 9.

Using ten frame cards, display the ten next to the other numbers.

Teaching points

Teacher has a full ten frame on a card plus cards representing numbers 8 and 9.

Questions

How many have we on this card?

How many on the two cards (showing 10 and another card)?

How do we say this in vernacular?

Explain it. How do we say it in English?

Can we say it another way in English? (eighteen, or one ten and eight)

Student practice and activity

Students write 11 to 17 then the English words to explain its meaning and a diagram such as the ten frame pattern. Stones can also be used to model the numbers.

Question examples

How do we represent 14? What does this mean in English? How can we make up 14 using a combination of numbers?

Is there another way?

Evaluation

Discuss how the numbers for 11 and 19 are the 10 plus 1 to 9.

Using ten frame cards, display the ten next to the other numbers.

Ask students to make numbers up to 100 using the ten frames

Questions

How do we represent 16?

How do we say this in vernacular?

Explain it.

How do we say it in English?