How do you use letters to represent language? What can be represented by letters?

As we all know, letters can represent phonemes, for example, in English, the vowel letters a, e, i, o, and the number of acacia u represent vowels, and consonant letters are used to represent various consonants. But letters can also represent numbers.

Letters can represent any number, but only one number can be represented in a question. It can also represent a formula with a specific meaning, a certain number that meets the requirements, or even a number with certain laws, in short, the letter can concisely represent the quantity relationship. For example:

a can represent a set; f(x) is a function of x, and so on.

1.When using letters to represent numbers, numbers are multiplied by letters, letters and letters, and the multiplication sign in the middle is often omitted; Or use "·" dots).

2.When multiplying letters and numbers, the multiplication sign is often omitted and the number is placed before the letter. However, when 1 is multiplied by a letter, the multiplication sign is not written, and the friend 1 is not written.

3.When a division occurs, it is expressed as a fraction.

4.If the result contains addition and subtraction, the unit should be added with a parentheses.

5.When the coefficient is a band score, the band score is turned into a false score.

The correct pronunciation of the 28 letters of Arabic:

There are a total of 28 letters in Arabic, but there is a very special language symbol "Heimzai", which is the most special and complex way of writing. Unlike the English alphabet, each Arabic alphabet has its own alphabet name.

In addition, each Arabic alphabet generally has 4 ways of writing (single, initial, middle, and ending), 12 pronunciations (mute, 3 short sounds, 3 long sounds, 2 soft sounds, 3 nasal sounds), and 4 forms of case (nomiative, accusative, genitive, and cive).

Alphabet composition

Arabic belongs to the Semitic language family of the Semitic language family, and is a phonetic script composed of 28 consonant letters and 12 diacritics (excluding diacritics). The writing order is written horizontally from right to left, and the reading order is also from right to left. The Arabic alphabet is not uppercase or lowercase, but there are typographical, handwritten, and artistic scripts.

When writing, each letter is written in a single or consecutive way.

Arabic has 28 letters, all of which are consonants. The vowels do not have letters (in fact, the letters and represent i and u, the letters y and i are different symbols, and u and w use the same symbol), and special symbols are used in the Arabic alphabet when they need to be marked, the first column is the way to write, the second column is the Latin transcription, and the third column is the pronunciation of the Arabic name of the letter.

Reference: Encyclopedia - Arabic Alphabet.

(1) A project is completed by team A alone on day A and team B on day B. The number of days that the two teams work together to complete. （ ab/a+b ）

2) 3 times the sum obtained by a and 7 divided by the quotient of 5. （ 3(a+7)/5 ）

3) The quotient of n divided by m. （ m/n ）

Figure Dust Ridge Yu faction rolling Ye Heng.

The first question is not A, it should be C