This chap looks really fierce.

这个人样子真凶。

《新英汉大辞典》

This heat is really fierce.

这样的高温真叫人难受。

youdao

A floppy hat is always good sense in summer, for the sun is really fierce.

夏天戴一顶松软帽是很明智的，因为太阳确实很炽烈。

youdao

He was really fierce.

BBC: Malcolm Webster

Mr. JIM HALL (AutoPacific Inc.): The competition in the market really is absolutely fierce.

NPR: Auto Watchers Underwhelmed by U.S. Designs

He courageously pursues the instincts of his imagination, whatever the cost may be and in this case the cost is high, since a tale stretching over thirty years needs a fierce narrative push that he cannot really muster.

NEWYORKER: Map of the Human Heart