it is... that.

e.g.
A rocket takes digital satellite Afristar into the sapce.
It's the first of two satellites that are helping an Ethiopian-American businessman transform the lives of million.
这句的It's ... that...是属于什么句型呢？强调句？that后面句子不完整？
主语从句的话that后面应该可以形成一句完整的句子吧？are helping an Ethiopian-American businessman transform the lives of million.缺少主语?所以不应该是主语从句，IT不是形式主语？是实意的？指代前面说的内容？

另：It is amimals and plants which(定语从句) live in or near water whose remains are not likely to be perserved, for one of the neccessary condition of preservation is quick burial, and it is only in the seas and rivers, and sometimes lakes, where(定语从句) mud and silt have been continuously deposited, that??? bodies and the like can be rapidly covered over and preserved.

it is imperative that? It is reported that...... it is ordered that,it is proposed that是什么意思 It is proper that 句型 celine-that is the way it is It is said that that was all that he said. so that it is definite that who is right it is likely that /it is probably区别 it is,that is,there is的区别是什么 It seems that his health is ( ).