This is a poem from the Greek Anthology, rendered into Latin by Hugo Grotius (1583-1645; you can see his edition of the Greek Anthology in Latin at Google Books).
Fel Fiet Si Nimium
Omne nocet nimium: vetus est sententia, nam quod
Mel fuerat, fiet fel tibi, si nimium est.
The vocabulary is keyed to the DCC Latin Vocabulary list. There are two words in this poem that are not on the DCC list:
fel (fellis, n.): gall, bile, bitterness
mel (mellis, n.): honey
fīō fierī factus sum: become
nam or namque: for, indeed, really
nimius -a -um: too much, excessive; nimis or nimium: excessively
noceō nocēre nocuī: harm
omnis -e: all, every, as a whole
qui quae quod: who, which, what / quis quid: who? what? which?
sententia -ae f.: opinion, judgement
sī: if
sīc: in this manner, thus; sīc . . . ut: in the same way as
sum, esse, fuī: be, exist
vetus veteris: old