一、根据汉语提示完成句子
1．About three ________(四分之一) of the earth is the ocean.
2．It's not always ________(安全的) to shop online.
3. I like ____________ (春天) best because the trees are green and the flowers come out.
4．The little girl ________(害怕) to go out because it was dark and rainy.
5．I wonder ________(是否) it is hot all year round in Singapore.
