The word shall is used to indicate mandatory requirements strictly to be followed in order to conform to the Specification and from which no deviation is permitted (shall equals is required to).

shall 一詞用于表示為符合規(guī)范而必須嚴(yán)格遵守的強(qiáng)制性要求，并且不允許偏離（shall equals is required）。

The use of the word must is deprecated and shall not be used when stating mandatory requirements; must is used only to describe unavoidable situations.

必須 一詞已被棄用，不得在說明強(qiáng)制性要求時(shí)使用； must 僅用于描述不可避免的情況。

The use of the word will is deprecated and shall not be used when stating mandatory requirements; will is only used in statements of fact.

will 一詞已被棄用，不得在陳述強(qiáng)制性要求時(shí)使用； will 僅用于事實(shí)陳述。

The word should is used to indicate that among several possibilities one is recommended as particularly suitable, without mentioning or excluding others; or that a certain course of action is preferred but not necessarily required; or that (in the negative form) a certain course of action is deprecated but not prohibited (should equals is recommended that).

應(yīng)該一詞用于表示在多種可能性中推薦一種特別合適，不提及或排除其他； 或者某種行動(dòng)方案是首選但不一定是必需的； 或者（以否定形式）不贊成但不禁止某些行動(dòng)方案（建議應(yīng)該等于）。

The word may is used to indicate a course of action permissible within the limits of the Specification (may equals is permitted to).

可能一詞用于表示在規(guī)范范圍內(nèi)允許的行動(dòng)過程（可能等于被允許）。

The word can is used for statements of possibility and capability, whether material, physical, or causal (can equals is able to).

can可以用于可能性和能力的陳述，無論是物質(zhì)的、物理的還是因果關(guān)系（可以等于能夠）。