1) before two a) one b) two 2) before three a) one b) two 3) before four a) three b) two 4) after four a) five b) three 5) after five a) four b) six 6) before five a) four b) six 7) before eight a) seven b) nine 8) after eight a) seven b) nine 9) after six a) seven b) five 10) after seven a) eight b) six

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