auld
daut
dawt
dual
duly
duty
lady
latu
laud
wady
waly
waul
waxy
yald
yaud
yawl
Four letter words that can be made from the letters in 'syringe' are:greygringyrereinringrisesignsinesingsire
Four letter words that can be made from the letters 'nfwade' are:anewaweddawndeafdeanfadefawnfendwadewandwaneweanwend
Jerk.
dry
Four letter words that can be made from the letters 'monastery' are:amenantearmyatomearneasteasymanemanymareMarsmartmastmatemeanmeatmesamoanmoatmoremostmotenamenearneatnestnosenosynoteomenrantratereamrentrestroamroanroserosyrotesamesanesateseamsearseatsentsnotsoarsomesoresortstarstaystemtametaretarntaroteamteartermterntometonetoretorntramtraytreytroytsaryarnyearyore
Some four letter words you can make from the word "syllabus" are ally, busy, bass, bull, and ball.
team mate tame
You can do even better than just five words!arborardorbardsbarfsbaudsboardboarsborasbradsbroadburasburdsburroburrsbursadarbsdaubsdobradorrsdorsadouradrabsdrubsdurasdurosdurradurrsfadosfardsfarosforbsfordsfoursfraudfubarfurorroadsroarssarodsofarsudorsurra
Post, as in postcard and posthaste.
Four letter words that can be made with the letters 'irbegd' are:bergbidebierbirdbredbriebrigdiredribgirdgridrideThose letters will also spell the word 'bridge'.
Four letter words that can be made from the letters 'cat in the hat' are:acheacneantecanecant (also can't)catecentchatchinchitciteeachetchhatehathheathintinchitchneatnicetactteattentthanthatthenthintinetint
That is a trick question. You can't make a four letter word using all five vowels.