open letters

So long as X is compact manifold, it has finite open covering, using different letters to name every open set of open covering, only need to use finite character set, through dynamics, various symbol sequence were formed with using this character set.

f：X→X只要X是紧致流形，它就具备有限的开覆盖，以不同的字母命名各片覆盖，只需用到有限的字母集合，用这个字母集合可以通过动力学生成种种符号序列。

It is in accordance with the vowel letters, vowel combinations of letters, consonants and consonant-letter acronym in the open and closed syllable syllable pronunciation of the law of memory.

它就是按照元音字母、元音字母组合、辅音字母及辅音字母组合在开音节和闭音节的读音规律记忆。

A sequence of numbers or letters used to open a combination lock.

一串能打开号码锁的数字或字母.

In this connection , the two sides to require banks secured, open letters of credit.

就此, 双方要求银行作保, 开信用证.

They are in a position to open letters of credit and effect payment in yen.

他们可以开立信用证并且用日元支付.