Letter-writing as a farm of social speech is an essential part of communication. It carries the principal functional language elements for realizing the communication art: 1) syntax (e.g., expressing a polite request using will or would in the interrogative form of a sentence), 2) attitudes (requests, acknowledgement, gratitude, regret, favour, etc.), 3) modality (probability, possibility, desire, etc.), 4) guide words that -enable the writer to connect his ideas, concepts, thoughts, etc. (e.g. as to, in comparison with, in respect of, etc.).
Letters, as is known, may be private, official (semi-official), professional. Each letter-writer has a characteristic way of writing, his style of writing, his manner of expressing his ideas, thoughts, facts, etc.; but it must be emphasized that the routine of official, business,. professional letters requires certain accepted idioms, phrases, patterns which are found in general use to-day.
Therefore, certain letter-writing skills must be acquired by practice, and details of writing must be carefully and thoroughly learnt. The purpose of the Manual is to convey to the letter-writer those skills through the specimens of letters presented herein.
Letter-writing, of course, is not the same as casual conversation, it bears only the same powers of thoughts* reflections and observations as in conventional talk, .but the form may be quite different. What makes the letter attractive and pleasing is not always the message of the letter, it is often the manner and style in which the message is written. For example, "I wish to express to you my sincere appreciation for your note of congratulation" or "I am "sincerely happy that you were elected President of the Biological Society." As you see such formulations show the attitude of the writer, his respect and sincerity.
The language of business, professional and semi-official letters is formal, courteous, tactful, concise, expressive, and to the point. In the case of "scientific correspondence" (we take the liberty to call it so), the majority of letters bear mostly a semi-official character and are concerned with different situations associated with scientific activities concentrated around the organization of scientific meetings (congresses, symposia, workshops, etc.), the arrangement of visits, invitation, publication, the exchange of scientific literature, information, etc. Letters of this kind have a tone of friendliness, politeness, naturalism. Modern English letters should not be exaggerated, over-
