Supposing
If
adverb
The kanji itself means temporary. When you add the に, we're asking you to imagine a situation temporarily, so the meaning changes to supposing or if.
The reading is kun'yomi, so here's a mnemonic to remember it:
If you don't mind, could you carry (かり) this for me? Supposing it's not too much trouble, of course.
仮にする
suppose someone does something
仮にやる
suppose someone does something
仮にできる
supposing something can be done
仮に明日雨だったら、ピクニックは中止になる。
Supposing it rains tomorrow, the picnic will be canceled.
仮に大学に入学できなかったら、父の会社に入社するのも一つの手だと思っています。
Hypothetically, if I can't enter university, I think joining my father's company is also an option.
仮に、このベッドが草で出来ていたとしたら、牛たちに食べられてしまったかもしれないよ。
If this bed was made of grass, it might have been eaten by cows.