Lesson 1.6 · Unit 1 · Communication: interpretive
Counting from thirty-one to one hundred
After thirty, the numbers stop being irregular. There are seven round tens to learn, and every number between them is built from three words in the same order. That makes this the easiest stretch of the number system, and it ends with one small surprise at 100. Phone numbers, ages of older relatives and prices all live in this range.
- Learn the tens. treinta (30), cuarenta (40), cincuenta (50), sesenta (60), setenta (70), ochenta (80), noventa (90). Most are the unit plus -nta: cincuenta, sesenta, setenta, ochenta, noventa. Thirty and forty are the two to learn separately.
- Between the tens use three words. Ten, then y (and), then the unit, with spaces: treinta y uno (31), cuarenta y cinco (45), noventa y nueve (99).
- Only 16 to 29 are single words. From 31 on, never write the number as one word. Cuarentaicinco is wrong and cuarenta y cinco is right.
- The words for 100. Exactly one hundred is cien. For 101 to 199 the word becomes ciento: ciento uno (101). Lesson 8.3 takes the numbers above 100 further.
- Uno changes before a noun. Treinta y un libros and treinta y una mesas. The final uno becomes un or una to agree with the noun.
- Say phone numbers in pairs or groups. A number like 555-1234 is often read in short groups: cinco, cinco, cinco, doce, treinta y cuatro. Listen for the grouping the speaker uses and write what you hear in digits.
- Check by adding. The tens count in jumps of ten, so cuarenta más treinta son setenta (40 + 30 = 70). A quick sum aloud is the best test of whether you know the words.
- Stress and spelling. Treinta, cuarenta, cincuenta, sesenta, setenta, ochenta, noventa are all stressed on the next-to-last syllable and need no accent. The c in cincuenta is an "s".
Where students lose marks: writing 31 to 99 as one word, or forgetting y. The structure is always tens, y, units, in three words. Also, do not use cien in 101: it is ciento uno.
The problem. Write 47, 68 and 100 in Spanish. Then write the sum "Thirty-five plus forty-four equals seventy-nine" and "I am thirty-one" with the correct age structure.
Step one: 47. Tens first: 40 is cuarenta. Then y, then 7 is siete: cuarenta y siete.
Step two: 68. 60 is sesenta and 8 is ocho: sesenta y ocho.
Step three: 100. Exactly 100 is cien. It does not take y.
Step four: the numbers in the sum. 35 is treinta y cinco, 44 is cuarenta y cuatro, and 79 is setenta y nueve.
Step five: connect them. "Plus" is más here, since y is already busy inside the numbers. "Equals" is son.
Step six: write the sentence. Treinta y cinco más cuarenta y cuatro son setenta y nueve.
Step seven: the age. Age uses tener and años: Tengo treinta y un años. The final uno becomes un before años, a masculine plural noun.
Step eight: check. 35 + 44 = 79. All numbers from 31 up are three words with y, and cien is the only form for exactly 100.
Problems 1 to 5 are routine. Problems 6 to 10 are multi-step or ask for reasoning.
- Write 40 in Spanish.
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cuarenta
- Write 33 in Spanish.
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Tens, y, units, in three words. treinta y tres
- Write 56 in Spanish.
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50 is cincuenta and 6 is seis. cincuenta y seis
- What is setenta y cuatro in digits?
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70 and 4. 74
- Write 100 in Spanish.
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Exactly one hundred uses cien. cien
- Write the answer in Spanish words: cuarenta y dos más veinte son ___.
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42 + 20 = 62, and 62 is sesenta y dos. Cuarenta y dos más veinte son sesenta y dos.
- Say "I am forty-one years old" in Spanish.
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Use tener with años. The unit uno becomes un before años. Tengo cuarenta y un años.
- Find the error: Mi abuela tiene setentaiocho años.
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From 31 on the number is three words, not one. Setenta y ocho is correct. Mi abuela tiene setenta y ocho años.
- You hear a phone number: seis, cuarenta y cinco, ochenta y siete. Write the digits.
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6, then 45, then 87. 6-45-87
- Write the numbers 90 and 99 in Spanish and say how they differ in form.
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90 is noventa, one word. 99 is noventa y nueve, three words with y. Round tens are one word, and everything between them is three. noventa; noventa y nueve