Constrained

We are constrained to and restrained from an action.

The government finances are severely constrained because of falling tax revenues.

I felt constrained to help her.

I was constrained to tell a lie.

Let me add some words about sentence fusion. A human is given two sentences and asked to produce a single coherent sentence that contains only the important information from the original two. This is a highly constrained summarization task. Investigations — carried out by Hal Daume and Daniel Marcu — has shown "that even at this restricted level, there is no measurable agreement between humans regarding what information should be considered important."

They are constrained by diplomatic protocol.

I am constrained by lack of time.

Vertical mixing is constrained due to the separation from the mixed layer by depth.

The epistle is opened and read—with a little wonder, most probably not a little vexation, at its constrained style.