一组合体的三视图如图所示，该组合体是由哪几个几何体组成，并求出该组合体的表面积（单位：cm2）．
水土流失严重的高原是（ ）
On Sunday morning. The sun is shining. We have no classes. We are playing in the park. Some girls are singing and dancing under a big tree. Some boys are climbing the hill. Tom is drawing near the lake. Mike and John are swimming in the lake. Where are Betty and Mary? They are sitting under a small tree. They are reading a book. We are very happy.
—_____ Even though the weather is very bad.
