Global warming ________ cause huge climatic changes and possibly a new ice age.

I’m looking forward ________ a trip to Mount Tai. [ ]

It’s already 10 o’clock. I wonder how it____that she was 3 hours late on such a short trip.

It is often said that home is _______ the heart is and now part of my heart is with my new classmates.

g back upon my teaching career, I don’t remember ever having been doubted, or challenged in class, ________ rejected.