You can chill a lot of things in the refrigerator, but don't put in too many or they won't get cold.
Don't put too many things in the refrigerator or they won't get cold.
You can chill a lot of things in the refrigerator, but don't put in too many or they won't get cold.
(冷蔵庫に物(食材)を沢山冷やすことができますが、沢山入れると冷えません)
冷蔵庫はrefrigerator、短縮でfridgeといいます。
chillは「冷やす」という意味で、get coldは「冷える」です。
thingは「物」という意味ですが、この場合で「食材」としてなります。
don't put in too many or they won't get coldのorというのは、otherwise(さもなければ)と同じ意味です。
また、省略した文なら文の後半の
Don't put too many things in the refrigerator or they won't get cold.
だけを使っても大丈夫です。
If you put lots of things in your freezer, they freeze better, but if you put too many things in your fridge, they won't stay cold.
この場合、次のような言い方ができますよ。
ーIf you put lots of things in your freezer, they freeze better, but if you put too many things in your fridge, they won't stay cold.
「冷凍庫にいっぱい物を入れるともっとよく凍るけど、冷蔵庫に入れすぎると冷えなくなる」
to freeze「凍る」
to stay cold「冷えたままの状態である」
ご参考まで！
アメリカ合衆国 
カナダ 
