连词成句。

1.  water,  where,  come,  does,  from    

                                                        ?

2.  put,  under,  it,  sun,  the    

                                                        .

3.  how,  plant,  you,  tree,  a,  do   

                                                        ?

4.  for,  flower,  wait,  a,  to,  grow    

                                                        .

5.  the,  seeds,  a,  in,  put,  pot      

                                                        .     

6.  you,  see,  sprout,  can,  a,  in,  days,  several

                                                                        .

内部换热式氨合成塔可分为三套管并流合成塔，单套管并流合成塔，双套管并流合成塔。