than is a comparison while then is used to say after this...

eg. than- I think that eggs are better than milk.

then- I went to the park and then i went home.

There is no limit, other than practical ones of retaining legibility.

to catch polkia you need to go to mt.corenet and find the top floor and theres polkia!

3 1/2

The fraction 9/19th is only 1/38 less than 1/2.

Always, always, a Thank You note , preferably handwritten, and in a timely fashion. If it's weddindgor shower gifts, please mention the item and say how lovely/usefiul/ thoughtful/ generous it was. E-Thank You is less deirable, but better than nothing if you are legitimately pressed for time.