Collocations for efficient - adj.

appear, be, look, seem, sound | become | make sth

extremely, highly, really, remarkably, very | fully, perfectly
The procedure is not fully efficient: improvements could be made. | We already have a perfectly efficient system - why change it?

increasingly | fairly, pretty, quite, reasonably, relatively | briskly, quietly
The receptionist was briskly efficient. | A quietly efficient manservant brought them coffee and brandy.

formidably, incredibly, superbly, supremely
His secretary was formidably efficient: her minutes were works of art.

economically, mechanically, technically

at
Their equipment was not as efficient at finding gold as today''s machinery.

in
The heating system is very efficient in its use of of fuel.