The NGram is rather persuasive for using "at nighttime" but I concur with Brian Fink that hyphenation is dying in favor of two-phrase usage (see what I did there?) and I feel it is a huge oversight. Hyphens can immediate and associate the this means of a phrase which is completely shed whe

Modern day dogs also Enjoy a big part as services dogs, therapy dogs and psychological support animals. Tutorial Dogs or Seeing Eye Dogs assist people with eyesight loss navigate obstructions. In that study, dogs were being set into conditions where they ended up framed for carrying out one thing