题目内容：

阅读下文并回答问题。

There are 24 solar terms (节气) in China, and the Grain Rain(谷雨) is one of them. It falls on April 19 this year.

This solar term is called the Grain Rain because it is known for “rain” that helps the grain grow. From its name, we can guess it means a time of more rain. So if you go out in the next two weeks, you may need to bring an umbrella with you.

But this is a great time for planting crops. If you miss the time for planting during the Grain Rain, you will feel sorry later. So maybe you can try to plant some flowers or vegetables in your garden. When the spring rain falls, farmers begin to grow crops (庄稼). Farmers often say, “Spring rain is as precious (珍贵的) as oil.” It brings farmers hope for a good year ahead.

There are also many interesting customs during the Grain Rain. In the northern part of China, people like to eat Chinese toon (椿芽) mixed with eggs. The food made during the Grain Rain tastes wonderful and is good for your stomach. In the southern part of China, the tea leaves are picked during the time. They are called Grain Rain tea, which is famous for its freshness and sweet smell.

1.How many solar terms are there in China?

2.Is it necessary to take an umbrella during the Grain Rain?

3.What is Grain Rain tea famous for?

4.Why is it a great time for planting crops when the Grain Rain comes?