He __________ (粗略地) outlined the plot of the opera.
He stayed under water for two minutes, and then swam to the __________（表面）.
The young scientist is __________（怀疑）about the theory.
You are easy to be __________（攻击）when you are in red in the forest.
他从踢足球中享受到了极大的乐趣。
He __________ __________ __________ __________ __________ playing football.
__________（自然地），I get worried when things go wrong.