The job of tracking the boys' movements proved slow and tedious.
This method proved too slow to keep pressure on retiring enemy forces.
However, the return to productivity in rural areas is proving difficult and slow.
Despite being urged by Alvinczi to attack again, he proved very slow to follow up his success.
I do have faster means at my disposal, however, if that proves too slow.
Other promising ideas have proved slow to come around.
Tracing back along the chain might prove difficult and slow; but, in a sense, it wasn't necessary.
Tourism is proving very slow to recover across the region.
Customers for the plant are proving slow to come forward.
Although most governments have pledged to sell off their shares in these companies, that process will probably prove slow.