English problems

The second space is between a and of, so we can know to fill a noun, and the noun form of combination is combination.

The fourth space should use which, not but.

Because there is no noun after they can't get away from it, it can be judged that this should be an attributive clause. Here, this is used to replace the first coke.

But it can only be used when it is followed by a complete clause.

The fifth empty cell should be filled with limited, where limited is used to modify the property of benefit.

The past participle as an attribute indicates passive meaning, and the present participle as an attribute indicates active meaning. Obviously, benefit can only be "restriction", not "active restriction", so the past participle limited is used as the attribute.