They see no particular reason to emphasize certain speeds more than others.

For example, consider throwing a rock upward at a certain speed.

But there's nothing which says that once the wind goes above a certain speed then the game is in jeopardy.

As the wave is traveling down the system, it travels with a certain speed.

The engine only starts once the vehicle has passed a certain speed.

"But there's nothing saying you can't accelerate at a certain speed."

When the wind passes a certain speed, the bridge closes.

The primary motion is accomplished at a certain cutting speed.

"Our program enables him to sustain a certain speed for a long period of time."

It had low drag, but was stable at only a certain speed.