"そして and すると" The difference is rather simple. - そして: and then; therefore. Think of it as そう して = (after/because something is done), ...; as a result of something. - すると: if you do that... It is like そう すると or そう したら = if you do that, then (something will happen). * The key is in -て (and as a result) and -と (if something) - they appear all over the place with these senses. So the two are almost never interchangeable. • 夫人は、椅子から立上った。そして、扉の方を見た. => The husband stood up from the chair, then looked in the direction of the door. • 緑のボタンを押して下さい、すると明かりがつきます. => Please push the green button. (If you do that, as a result) Then the light will come on. そして describes a situation where something's already been done and after/because of that another thing follows. すると means nothing's been done yet, and that if it is done, there will follow another thing as a consequence. So すると typically makes the condition in a conditional statement. For example, もしかすると means "perhaps / possibly / maybe". By comparison, そして is about something concrete. After/since something happened, or given some fact/result/state, then (something follows).