As we all know (介词短语),
there(主语） are(动词） four seasons(宾语)
[in a year] 介词短语.

Different seasons(主语) have(动词) different features(宾语). [2a]

In spring (介词短语), (介词短语）
the weather(主语） starts(动词） [to get warm]. [4]

The wind(主语) blows(动词) gently(副词). [7 句尾]

It(主语) often(副词) rains(动词). [7句中]

Plants(主语) starts（动词） [to grow]不定时. [4]

Everything(主语） turns（连接动词） green（主语补语：形容词）. [3]

It(主语) is(帮助动词） exciting（主动词） （现在进行时）
to [take a trip] or [fly a kite] (不定时）
[in the open air] (介词短语)
[in spring] (介词短语)

It(主语) is(连接动词) very hot [3]
[in the summer]. (介词短语)

The sun(主语) shines（动词） brightly(副词).

Many people(主语)
like （动词）
to [go to the beach] and [swim in the sea]
[with their friends]. (介词短语)

It(主语) is(连接动词) nice (主语补语：形容词)
[to eat ice cream] (不定时短语)
[in the hot weather]. (介词短语)