Example sentences of "but it is often [adj] [verb] " in BNC.

  Next page
No Sentence
1 Soil pipes from downstairs WCs may be connected to the main soil stack of a single-stack system , but it is often better to connect them directly to the underground drains .
2 They fry can be left with the parents until they attain anything up to one inch in length , but it is often advisable to remove the parents long before this .
3 A chance finding , outside the mainstream of scientific research , can sometimes be very valuable , but it is often difficult to see its potential .
4 But it is often difficult to judge .
5 Other places were also hit savagely from time to time , but it is often difficult to tell from the registers which particular disease was responsible for an unusually high number of deaths .
6 By changing the excitation frequency we can probe the upper-state vibrational levels , but it is often difficult to identify the ν'=; 0 level , which may have low probability of excitation or emission .
  Next page