In this example, "visible" (adjective) is not approved and was replaced by "see" (verb). But to be able to use "see", it was necessary to replace "must be" by "make sure that you can".
 
 As in word-for-word replacements, you must make sure that the word you choose is suitable.
 
 Example:
 
 Instead of: UCycleU the unit twice to remove air from the lines. (verb)
 WRITE:  Operate the unit for two UcyclesU to remove air from the lines. (noun)
 NOT:  Make two cycles of the unit to get air out of the lines.
    (CYCLE is a function of the operation of the unit - that is, what it does, not what it is.)

 
UReason 2U: The direct "translation" of the unapproved word leads to something that is meaningless.
 
 Example:
 
 Instead of:  This compound is Usemi-toxicU.
 WRITE:  This compound is Upoisonous in some concentrationsU.
 NOT:  This compound is half-poisonous.
    (Something is either poisonous or it is not poisonous. It cannot be "half- poisonous".)

 
 Example:
 
 Instead of:  Without this modification, service lifeUmay be uncertainU.
 WRITE:  WIthout this modification, Uit is possible that the service life will be shorter than usualU.
 NOT:  Without this modification, you will not be sure of the service life.
    ("Uncertain" means either "unknown" or "not sure".)

 
UReason 3U: You cannot find a suitable, simple alternative, and you must reformulate your ideas.
 
 The fact that you cannot find a suitable alternative is often a sign that:
 
      Your ideas are not sufficiently clear in your own mind, or
 
      You are thinking in terms of words, not ideas, or
 
      You are not being sufficiently specific, or
 
      What you are trying to say is not necessary.
 
 Remember: words are only symbols that we use to express ideas. If your ideas are confused, you will not use the symbols (words) effectively. Conversely, if you attach too much importance to the symbols, you will lose sight of the ideas you want to express, and your message will not be clear.
 
 In addition, Simplified English encourages you to make your instructions specific (Refer to Section 1). Therefore, if a word or group of words is too abstract, or if it implies several things, you will find it impossible to do a word-for-word replacement satisfactorily. In such cases, you must decide what the unapproved word really means, and then reformulate the specific ideas.