it is easy to_down on the ice.中间横杠填哪个单词

it is easy to_down on the ice.中间横杠填哪个单词 It is d____to walk on the thin ice. the ice is very thin.it's very easy to drop____when you skat The ice is __thin__skate on It is easy to climb the hill 和 I found it not easy to get on the ice is too thin ------ A to skate on it B skating on it The ice is too thin.You can'tskate on it.(改为同义句） The ice is The ice is to slippery to walk on it.后为什么加it the ice is to skate on. An ice cream is on the ground. The book is not easy .On the contrary it is rather difficult The ice is so thin that you can't skate on it