Professor White has written some short stories, but he is________known for his plays. 

The poor boy couldn't work the problem out. He wasn't ____ clever.

Everybody went to the opening ceremony of the film festival——_______ Francisco, who has no interest in anything but sports.

. --- Jack failed in the maths exam again. He’s too stupid.--- In my opinion, he’s __________ lazy than stupid.

Chemical pollution will bring about a threat to agriculture and food chain, and ________ to human health.