1. Mr. Wu invited Kitty ________ (join) their trip to the World Park.
2. It is very interesting for them ________ (remove) the snow in winter.
3. Suzy ________ (make) a snowman while Kitty was taking some photos.
4. If the temperature ________ (drop) to 0 ℃, the water will become ice.
5. Yesterday a young boy ________ (fall) from a tree and hurt his legs.