This and that can be used with adjectives and adverbs in the same way as so. This usage is very common in informal English.
- I didn’t realize that it was going to be this bad. (=I didn’t realize that it was going to be so bad.)
- I don’t think that he is that clever. (=I don’t think that he is so clever.)
- Was she that stupid to trust his again? (=Was she so stupid to trust him again?)
- I don’t understand why she should get this upset. (= I don’t understand why she should get so upset.)
Through is commonly used in American English to mean ‘up to and including’ a particular point of time.
- The park is open from May through October. (= The park will be open in May, June, July, August, September and October.)
- Our offices are open from Monday through Friday.
In British English, through is not used in this way. Instead, British people use to…inclusive or until the end of…
- The park is open from May to October inclusive.
- The park is open from May until the end of October.