• It was not until 30 years later that the study of these viruses became popular.

• It was another 17 years before the first engine was developed.

см. тж. до сих пор

• The laser used to date has required ...

• The gap between the two portions of Saturn's ring is called "Cassini's division" to this (or the present) day.

• The switch makes possible heretofore impractical applications of ...

• Huge reserves of ore, hitherto virtually untouched, will become available.

• To date our highest emitter power has been ... wt/cm[sup]2[/sup].

• This movement is observed to the present (or this) day.

• Until the present time few investigations have been conducted of ...

• Up to now, there has been no detailed work done to find ...