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

 Speaking of all the songs he has written, I think this is probably his __________ one. 

---You are devoted herself_____ to her research and it earned her a good reputation in her field.

The director added a few characters and changed some names in this movie but _______ this is a true story.

Yesterday evening when going to the cinema I frequented, I went in a wrong direction ___.