However, we can make a sentence using words that *sound* like they end in /f/ while including some with silent "e":
"The calf, in the rough, had a tough cough."
Here's the breakdown:
* calf: This ends in /f/ sound
* rough: This ends in /f/ sound
* tough: This ends in /f/ sound
* cough: This ends in /f/ sound
Let me know if you'd like to try another sentence with different constraints!