Different components of 
are expressed in different ways. More
specifically, steps are expressed by means of imperative, including
negative imperatives such as Do not torque. Each step is
composed of up to five action descriptions; connectives such as
and and then are used. Purpose and Until clauses
occur.
The style is somewhat telegraphic. This in particular affects Noun Phrases (NPs), that never include articles: therefore NPs may be ambiguous between definite anaphora and indefinite reference, as in (from Installation of Fuel Flow Proportioner):
1. (A) Lubricate two packings (MS28778-4) with hydraulic fluid and install on two unions.The issue is whether two unions in 2. refers to the same two unions in 1 --- this seems to be the case, given the concise style used in technical orders. However, note that normally coreference should be expressed by means of a definite article, as in the two unions.
2. (A) Install two unions. Torque to 143-158 inch-pounds.
In WARNINGs and CAUTIONs declaratives are used; modals such as shall and must frequently occur.
WARNING.Occasionally, in CAUTIONs imperative are used:Personnel working near aerial refuel receptacle shall use care to prevent personal injury from inadvertent operation of slipway door.
Do not operate equipment for more than 30 minutes without cooling air to prevent damage to electronic equipment. If power is to be reapplied without cooling air, allow a 15-minute cool-down period.
NOTES are the most varied in style: some are expressed as imperatives, others as declaratives.