1. This computer is such a slow thing that I can't use it.

Question

2. This computer is such a slow thing that i can't use.

(Which one is correct?)

3.This computer is so slow that I can't use it.

4. This computer is so slow that I can't use.

(Which one is correct? Are both OK?)

Answer 1

#1 and #3 are correct; #2 and #4 are incomplete.