"tighten securely" is correct English and can be used in written English.
For example, "Be sure to tighten the screws securely before using the appliance."
Always tighten the bleeder screw before letting up the peddle; final check that it is tightened securely when finished.
Make sure that you are using the right blade and that it's correctly seated and tightened securely.
If your girth is tightened securely, you can also hold onto the pommel without your saddle slipping but never let go of your reins, the reins keep control of the horses shoulders and if you have control of the horses shoulders, even if the horse falls you will never fall off.
Add a final nut on the outside of the second handle, and tighten it securely.
Put the big bolt back with the washer and tighten it securely.
Put the big bolt back with the washer/disk and tighten it securely.
Install new o rings on the refrigerant line fittings on the accumulator, then reconnect the fittings and tighten them securely.
Re-install the cord clamp and tighten it securely, then slip the cord boot into its slot.
Loosen the clamp, and pull the handlebars up, or slide them down until they are at a comfortable level, then tighten them securely.
However it is the responsibility of the surgeon to ensure the clamps are tightened very securely when the fixator has been applied as loose clamps are not infrequently responsible for loss of fracture control.
