综合填空。

     There are four seasons in a year: spring, summer, fall and winter. In spring, the weather is warm.

It is a good season for 1.            (hike). This is a 2.             (hope) season. Summer 3.             (come)

after spring. It is very hot. The children like to go 4.             (swim). It often rains and sometimes it

rains 5.             (heavy). In fall it is cool. It's a good time 6.             (go) hiking. The farmers are busy

7.             (harvest). The 8.             (leaf) fall from the trees. Winter is a very cold season in the year.

The wind blows 9.             (strong). Sometimes it snows, and we can make 10.             (snowman).

充血性心力衰竭病人的发绀可为

A．中心性发绀
B．周围性发绀
C．混合性发绀
D．血管性晕厥
E．阿-斯综合征