Si faire se peut = If possible.
Je n’en puis plus = I am done up, exhausted.
Je n’en puis mais = I cannot help it; It is no fault of mine. (See [Mais].)
Cela se peut = That may be.
Cela ne se peut pas = It cannot possibly be; It cannot be done.
On fait comme on peut = We must do the best we can; We have done the best we could.
Il est toujours on ne peut plus aimable = He is always as nice as can be.
Prêcher
Il prêche dans le désert = (lit.) He preaches to empty benches; (fig.) All his talking will not convince any one.